Introduction
I see some new faces out here. How many people are here for the first time? Okay, about half of you. Cool. How did you guys find out about us? Facebook? Yeah? Awesome.
Well, welcome, everybody. My name is Mark. I’m the pond guy around here, but we have a wonderful, huge staff of people who put everything together.
My role today is basically to teach you all the stupid things I’ve learned over the years—what not to do when building a pond, what not to do when taking care of plants, and what not to do when taking care of fish.
I’ve been doing this for about 30 years. I give these seminars all the time, but I learn something new at every single one, so hopefully you guys will, too.
And don’t hesitate to raise your hand if you’re thinking about a question. Your neighbor probably has the same question—or maybe they haven’t even thought about it yet, and you’ll help everybody out. So don’t hesitate to interrupt as we go through this.
I’ve always wanted to separate these into two seminars: a fish seminar and a plant seminar. But we run out of calendar because we want to do them all in the spring, and I just don’t have the energy to do them every single week. So we put them all together.
My goal today is not only to talk about plants and fish, but also to answer your questions about how to get a crystal-clear pond with happy, healthy fish without a lot of work.
If everybody got one of these little booklets, I always start by talking about our ponds and how we build them. Plants are an integral part of our ponds, and fish are an integral part of our ponds, but before we even get to plants and fish, there are a few basics we recommend when it comes to construction.
I like to get everybody oriented and on the same page, and then we can jump into all of your questions.
Pond Filtration Basics
I’ve been doing this for about 30 years. We first started building ponds back in the late ’80s. My mom and dad are in the back row there, and they allowed me to play in their backyard.
The first pond I ever built was at their house in the late ’80s, and we did not have a skimmer.
The first pond we built had a pump sitting at the very bottom. It was a high-maintenance setup. You’d have to scuba dive down to the bottom of the pond to unclog the pump and get all the muck and debris off of it.
Pond skimmers just weren’t around then.
It was around 1994 or 1995 that pond skimmers became available. A friend of mine out in Chicago, Greg Wittstock, started a company called Aquascape.
How many people have heard of Aquascape?
Aquascape today is the largest manufacturer of pond equipment in the world. We think they’re one of the most innovative companies out there, and we’ve been doing business with them since 1994. They’re a great company, and they continue to innovate.
There are other companies that manufacture skimmers, but we sell the Aquascape skimmer because we think it’s probably the best skimmer on the market when it comes to features, ease of installation, and overall performance.
The role of the skimmer is to move the pump from the bottom of the pond into the skimmer.
It’s similar to how a swimming pool works. If you get a leaf on one corner of the pond, the skimmer should be powerful enough to pull that leaf off the surface and into the skimmer basket before it drops to the bottom.
And it’s not just leaves. It’s twigs, sticks, solid fish waste, pollen—you name it.
The past couple of weeks, you probably walked out to your car and found an inch of pollen on it. Well, guess what? Those nutrients are getting into your pond.
You don’t really see it because it’s microscopic, but it adds a huge nutrient load to the pond if we don’t get it out.
If the skimmer is doing its job, about 90% of all the debris that gets into the pond gets sucked off the surface before it drops to the bottom.
So you could say that the skimmer is responsible for about 90% of the physical filtration of the pond.
If you don’t have a skimmer on your pond, adding one can solve a lot of problems. And if you have a rubber-lined pond, a skimmer can usually be retrofitted.
If you already have a skimmer but it doesn’t seem powerful enough, there’s a simple test I like to do: throw a leaf on the opposite side of the pond.
If the leaf just hangs out in the middle or never really makes it to the skimmer, you probably need a bigger pump to increase the flow.
Our skimmers also have these little doors that create a very high-efficiency, high-flow rate across the surface of the water.
So there are ways to improve the efficiency of your skimmer.
Physical Filtration vs. Biological Filtration
We have two types of filtration on a pond.
The skimmer is the first type, which we call physical filtration.
It’s physically removing all of that debris from the pond.
That’s also where most of your maintenance comes in.
Every once in a while—maybe once a week—you simply reach into the skimmer, empty the basket, dump the debris, and put the basket back.
Your pump won’t clog because it’s sitting down inside the skimmer.
You can keep that skimmer as clean as you want.
If you’re a bad pond owner like me, you might empty it every three months.
If you’re very meticulous, every time a leaf gets in there you’re like, “Oh my gosh! I’ve got my coffee—I’ve got to run out with tweezers and grab that leaf!”
But the skimmer is step one in filtering the pond: physically getting all of that debris off the surface and out of the water before it has a chance to interact with the pond.
We have different-sized skimmers for different ponds.
Anybody ever see the pond at Leg Up Farm?
We built that pond. I designed it. It’s a little over a third of an acre—between a third and a half an acre.
That pond has skimming filtration, but if you looked at our standard skimmers, we’d have to line up about 30 of them to handle that pond.
So we actually custom-built a skimmer for it.
We can custom-build skimming filtration into acre-sized lakes if necessary.
We’re also building a 100-foot-long pond outside the new Memorial Hospital. It’s right outside the emergency room and the main entrance.
That pond will have custom-built skimming filtration that’s basically hidden because we’re skimming a surface that’s 100 feet long.
The idea is always the same: we want to skim the surface so the debris gets out of the pond.
That pond is going to be open to the public basically 24/7, so it needs to look beautiful.
That’s step one: skim the pond as effectively as possible.
Biological Filtration
The second part of filtering the pond is the biological filter.
This is where the magic happens.
If we’re physically removing all of the debris, there’s still about 10% that makes it through—fish waste, organic material, and other things that eventually reach the bottom of the pond.
As those materials break down, they produce ammonia.
If fish were left swimming around in ammonia, they wouldn’t be very happy, and they wouldn’t survive very long.
The first thing we do with biological filtration is add what’s called beneficial bacteria.
It’s good bacteria that colonizes every nook and cranny throughout the pond.
If you notice our ponds, they have rock and gravel throughout them. Inside the filters, we have filter mats, bio balls, lava rock, and other materials that give beneficial bacteria places to grow.
A friend of mine did a study a number of years ago trying to determine what material grew the most beneficial bacteria.
What he determined was that those little plastic pots—Grubbies from the dollar store—grew bacteria better than anything else in the world.
Kind of makes you think about doing dishes!
The goal is to get beneficial bacteria to colonize everywhere.
The more bacteria we can grow, the more fish waste and ammonia we can process.
So when you’re asking, “How many fish can I have in my 10-by-10 pond?” or “How many fish can I have in my 50-by-50 pond?” the size of the pond itself isn’t necessarily the most important factor.
The size of the biological filter is more important.
If you have a huge biological filter on a tiny pond, you can potentially have a huge amount of fish.
If you have zero biological filtration on a huge pond, you’re going to be limited in the number of fish you can have.
It’s not simply the physical size of the pond that matters. It’s the size and efficiency of your biofilter and how much beneficial bacteria you can grow.
How the Nitrogen Cycle Works
Our biofilters have a swirl chamber on the bottom, filter mats in the middle, and then either lava rock, bio balls, or another type of biological media on top.
The bacteria sits there waiting for ammonia to come in.
As the ammonia comes in, the beneficial bacteria converts it into nitrites.
So here’s where the science lesson starts.
Ammonia → Nitrites → Nitrates
If the cycle stopped at nitrites, we’d have a problem.
How many people have been to Europe and seen water gardens there?
How green are they?
They’re green, right?
European ponds have traditionally been green. Europeans don’t necessarily care about crystal-clear water as long as the fish are happy.
Europe has been doing ponds much longer than the United States has existed. There are ponds dating back to Roman times. I just read an article about a 3,500-year-old pond in Turkey where they actually raised decorative fish.
So they’ve been doing this for a long time.
One major difference between many American ponds and European ponds is that Europeans are often perfectly happy with green water.
The fish are happy because we’ve gotten rid of the ammonia.
But if the biological filter is smaller, it may only be processing the ammonia into nitrites. The cycle stops there.
High nitrites feed green-water algae.
If you’ve ever seen a pond where you stick your hand into the water and your hand just disappears, that’s green water.
The fish don’t really care. They may actually like it because it gives them some cover.
But we’re crazy Americans. We want crystal-clear water because we want to see those expensive fish we bought!
The reason you have green water—whether it’s an acre-sized lake or a 10-by-10 pond—is high nutrients in the water, particularly nitrogen compounds that support the algae.
The solution isn’t necessarily to kill the algae.
Instead, we want to starve the algae by growing enough beneficial bacteria and plants to consume those nutrients.
Why We Don’t Rely on Algaecides
If you look at our ponds, they’re crystal clear all the way to the bottom.
The fish are happy because we’ve gotten rid of the ammonia.
The water is clear because we’ve created a biological system that processes the nutrients instead of allowing algae to take advantage of them.
We don’t use algaecides in our ponds, and we don’t use UV sterilizers.
Those things can work. They’ll kill single-cell algae.
But they don’t necessarily help balance the entire pond.
They kill the algae, but now you have dead algae in your pond.
And guess what?
Dead algae becomes nutrients for next week’s algae.
So next week you come back with a bigger bottle of algaecide, then a bigger bottle the week after that, trying to kill all the algae.
Instead, what we like to do is grow as much beneficial bacteria as possible.
We starve the algae instead of killing it.
Does that make sense?
So if you have green water, the question becomes: How do we grow more beneficial bacteria?
Maybe the physical size of your biofilter needs to be bigger.
Maybe you don’t have one at all.
Or maybe there’s room inside your existing filter to add more bio balls, lava rock, or filter media.
If water can escape around the sides of your filter, you’re losing filtration efficiency.
If there’s physical room to add more bio balls or lava rock, do it.
The more surface area you have available for bacteria to colonize, the more bacteria you can grow.
Don’t Clean Your Biofilter!
Our filters fit very tightly against the sidewalls.
Over two or three years, filter mats can shrink a little bit, allowing water to sneak around them.
That’s why it’s important to replace your filter pads every two to three years.
But our bio balls don’t need to be replaced. They can last forever.
If you look down into your biofilter, you’re going to see that it looks brown, mucky, and gross.
That’s a good thing.
I call it biofilm.
That’s beneficial bacteria living in your filter.
If you ever want your pond to turn green, go ahead and clean out your biofilter.
As soon as you clean it, you’re killing off the bacteria that’s doing the job of cleaning your pond.
We sell pond kits, and people go home and build their own ponds.
They call us a week later and say, “Mark, this is the worst thing you ever sold me! The pond is pea-soup green!”
I can usually figure out which one of the couple cleaned their biofilter.
That’s the problem.
So with our ponds:
Clean the skimmer as often as you want. Leave the biofilter alone.
The muck you see in there isn’t organic debris. It’s actually a living culture of beneficial bacteria doing its job.
It doesn’t clog the filter.
The water can still flow freely through all of that biological media.
So think of it this way:
Physically clean the skimmer. Biologically leave the biofilter alone.
Lava Rock vs. Bio Balls
Do bio balls float?
No.
We use both lava rock and bio balls.
In terms of how much beneficial bacteria they can support, they’re fairly similar. Bio balls have a slight advantage and can grow a little more bacteria, which is probably why they’re more popular.
But we have ponds that we built 15, 20, even 30 years ago that are still using the same lava rock.
Lava rock works.
It’s just not quite as effective as bio balls.
And you can absolutely use both.
If you have bio balls and think, “I need more filter media,” but you don’t have any more bio balls on hand, grab a bag of lava rock and mix it in.
That’s perfectly fine.
The key is to get as much surface area as possible so you can grow as much beneficial bacteria as possible.
Plants as Part of the Filter
Our biofilters are open, and if you notice, many of them have plants growing on top.
That brings us to plants.
Once the bacteria converts ammonia into nitrites, the bacteria processes those and ultimately produces nitrates.
Nitrates are fertilizer for plants.
If you go to Lowe’s and buy fertilizer for your lawn, one of the ingredients is nitrates.
So the plants consume those nitrates.
That’s how our filters are designed.
They’re hidden in the ground and softened with plants growing on top.
The entire process is:
Ammonia → Nitrites → Nitrates → Plants
That’s the whole science lesson!
The larger the pond and the more fish we want to raise, the larger the biological filter needs to be.
For example, the biofilter at Leg Up Farm is 30 feet by 50 feet—bigger than this tent.
Our large pond here has a biofilter that’s about 10 feet by 6 feet.
Our medium pond uses a smaller plastic biofilter, and our small pond uses an even smaller one.
What If You Don’t Have a Skimmer?
If you don’t have a skimmer and you’re not going to install one this year, just remember:
You are the skimmer.
You have to physically remove as much debris as possible.
Use a leaf net to remove debris from the bottom.
You can also rent pond vacuums.
Another great tool is a sludge cleaner.
This is another type of bacteria—an anaerobic bacteria—that works down at the bottom of the pond.
It eats away organic sludge and essentially converts it into simpler compounds.
It’s a great supplement even if you have a skimmer.
The skimmer gets most of the debris first, but the sludge cleaner helps polish off that other 10%.
So remember:
Beneficial bacteria is your friend. Biofilter is your friend. Sludge cleaner can help, too.
Brown Water and Pond Cleanouts
Brown water can be caused by excess debris on the bottom of the pond.
If your pond hasn’t been cleaned in a while, it’s probably time to clean it.
Our typical procedure is to put a temporary tank next to the pond.
We’ll pump about a third of the pond water into the temporary tanks and save it.
Then we’ll move the fish into those tanks.
After that, we’ll drain the pond the rest of the way down and physically remove all the muck and debris.
Our ponds are designed to look natural, but they’re actually closed ecosystems.
We’re trying to mimic nature as much as possible.
In nature, snow lands on the mountains. In spring, it melts and fills the rivers, creating a huge torrent that washes everything away.
We mimic that process in our ponds by doing a cleanout.
The reason we save about a third of the water—and sometimes more—is that we don’t want to destroy the entire ecosystem.
We want to save that established water.
Your fish are used to that water. They’re used to its pH, temperature, and chemistry.
We don’t want to shock them with a huge water change.
Even a 50% water change can be pretty dramatic.
Brown water can also come from things like dyed mulch.
I was at a customer’s pond recently. We had just cleaned it, and they called and said, “Mark, the water is brown!”
I went out there, and the landscapers had freshly mulched the entire area around the pond with dyed mulch.
They got a little rain, and some of that dye washed into the pond.
Sometimes you can simply wait and let it dissipate with additional rainfall.
Or you can use activated carbon to remove those tannins and the brown coloration.
How Often Should You Clean Your Pond?
For ecosystem ponds with a properly functioning skimmer and biofilter, we recommend a cleanout at least every three years.
Some customers have ponds in very leafy or wooded areas, or they completely neglect the pond from November through April. Those ponds may need to be cleaned every year.
But if your skimmer is doing a great job, you generally don’t need to clean the pond more than once a year—and often not even that.
We have customers who’ve had ponds for 10 years without a cleanout.
Their ponds look fantastic because they’re extremely meticulous.
But even then, I would recommend flushing the system periodically.
Maybe every five years in that situation.
Ten years is pushing it.
The skimmer-and-biofilter system is the best system out there, but it’s still not nature.
Stuff is going to accumulate.
Give the system a good flush every few years.
The majority of our customers probably clean their ponds once or twice every three years.
Fish Care
We do all of this to keep the fish happy and the water crystal clear.
Now let’s talk about fish.
This time of year, the fish are just coming out of their winter state called torpor.
It’s kind of like hibernation, but not quite.
Fish don’t technically hibernate. They enter a state of torpor.
They’re still alive and breathing, so we need to make sure gases can escape from the pond during the winter.
For winter, we recommend aeration, either with a waterfall or an aerator sitting on the bottom of the pond.
The air bubbles rise to the surface and break the surface tension, allowing gases to escape.
The fish aren’t eating during this period.
They stop eating when the water temperature drops below about 55 degrees.
Then, in the spring, when the water reaches about 55 degrees again, they’re basically saying, “All right, it’s springtime. I’m hungry!”
We want to start them on an easy-to-digest food.
At those early spring temperatures, food that sits in their digestive system for too long can potentially cause problems.
So we want to ease them back into feeding.
Spring Fish Food
The food I love to start our fish on is manufactured by Blue Ridge Fish Hatchery in the Carolinas.
It’s a probiotic food.
Coming out of winter, the fish are dormant, but so is everything else in the pond.
The plants are dormant. Many of the things that can attack the fish are dormant.
We want to build their immune systems as quickly as possible so they’re ready to fight infections and other problems.
That’s why I love starting them on probiotic food.
I also brought out koi crunchies.
Koi crunchies are a great way to teach fish to eat from your hand.
You hold them out and the fish will come right up and bite them out of your hand.
They’re also high in vitamin C, so they can help support the fish’s immune systems.
They’re an easy-to-digest treat, too.
So I usually start the season with probiotic food and supplement with some koi crunchies.
Oranges, watermelon, and similar foods can also make good treats.
Once we get into summer—around June and July—we switch to what I call a high-growth food or a color-enhancing food.
These foods are higher in protein.
They help add body weight and growth, while also enhancing the fish’s colors, especially the reds and whites.
Keeping Fish Healthy
Just like when we walk through a mall and think, “Don’t lick the door handle,” there are diseases and bacteria everywhere.
The same is true in your pond.
If your fish are happy, healthy, and vigorous, they’re generally able to fight these things off.
But if your pond conditions become unhealthy—your pH is out of balance, your nitrites or nitrates are elevated, or there’s not enough oxygen—the fish become stressed.
Once they’re stressed, they’re much more susceptible to disease.
So whenever someone comes in with a fish health problem, the first thing we talk about is water quality.
What’s happening in the pond?
Are you aerating enough?
Are you skimming enough?
Are you using beneficial bacteria?
Those are the natural cycles that help keep fish healthy.
The first thing we want to do is make the water as healthy as possible.
Then we help the fish fight whatever problem they’re dealing with.
One of the most natural things we can do is feed probiotic foods that help support their ability to fight problems from the inside out.
If we’re dealing with an emergency situation and we need to act more quickly, one of my first tools is pond salt.
Fish love salt.
It helps support their slime coat, and it can be useful for a number of common fish problems.
When we quarantine our fish before they’re sold, we use salt and bring the water up to about a 0.3% solution.
Quarantine Your Fish
We get our fish from very reputable sources.
In 30 years, we’ve never infected a customer’s pond with a virus or bacterial infection.
There are places where you can buy a fish that was in another country yesterday and is in your pond today.
You have no idea what you’re introducing.
We always know when something like that happens because we’ll suddenly sell out of a particular medication because everyone went to the same store and bought infected fish.
I’m not going to mention any names, but there are places out there that move fish very quickly without properly quarantining them.
So if you’re ever tempted to buy a fish somewhere else, ask about their quarantine procedure.
If you ask them where their fish come from and what their quarantine process is and they just stare at you blankly, walk away.
You don’t want to introduce disease into your pond.
There are serious diseases out there.
Koi herpesvirus, or KHV, is one example.
If KHV gets into a pond, it can wipe out your fish very quickly.
There are researchers working on these diseases, but they’re still a serious concern in the hobby.
So be careful about where you purchase fish and make sure you’re buying from someone who takes quarantine seriously.
Do You Need to Test Your Pond Water?
How often should you test your water?
We do offer water testing here. We’ll test pH, nitrites, and other parameters.
But in 30 years of owning a pond, I’ve never professionally tested a customer’s pond that had a functioning ecosystem.
In my opinion, it’s not necessary if everything is happy and healthy.
Let nature do its thing.
We do have customers who love testing their water.
They’ll test it in the morning and then test it again at night.
Your pH can be different in the morning than it is at night.
But once you start trying to micromanage all of those numbers, suddenly your pond isn’t relaxing and low-maintenance anymore.
You’re adding pH up in the morning, pH down at night, and constantly tinkering with the system.
We find it’s much easier to let nature take care of it.
That being said, we test our tanks regularly because our tanks aren’t balanced ecosystems.
We might have five fish in a tank one day and 500 the next.
So we have to micromanage those systems.
Our ponds, on the other hand, are functioning ecosystems.
The more you tinker with them, the more they become your headache instead of letting nature take care of them.
Treating Sick Fish
Salt is definitely a big first step.
After that, we have specific remedies for specific problems.
But one thing I don’t recommend is taking a sick fish out of the pond and putting it by itself.
He’ll be sad.
You guys laugh, but he’ll be sad!
If you put a sick fish with a couple of healthy buddies, we’ve seen them heal much better.
We’ve seen it happen many, many times.
So that’s something to think about.
Pond Predators
Now let’s talk about predators.
Herons, bald eagles, all kinds of birds, and mink.
Anybody ever seen a mink?
Mink are around everywhere.
We built a pond for some people about 15 years ago. They had a beautiful property with several huge interconnected ponds filled with gorgeous Japanese koi.
The smallest pond was about the size of our tent.
We even built fish caves underneath some of the large stepping stones so the fish could hide.
The following year they called me and said, “Mark, all the fish are gone.”
I said, “No, they’re not. Come on. We built fish caves underneath there!”
So I went out there, grabbed a fish net, and started checking underneath every fish cave.
There wasn’t a single fish in the pond.
Finally, the farmer next door came over and said, “You guys see that mink over there?”
I said, “A what?”
I’d never even thought about mink.
That was my first real exposure to them.
Since then I’ve educated myself about mink, and it turns out they’re in all 67 counties in Pennsylvania.
They’re here year-round.
If a mink sees your pond and it’s hungry, it can clean out your pond in about two or three hours.
It’ll swim in, grab a fish, take it back to the den, come back for another fish, and repeat the process.
In two or three hours, it can get every last fish in the pond, down to the tiniest fish.
Every winter we get calls from certain neighborhoods.
Someone will say, “Mark, somebody came and stole all my fish! I’m going to call the police!”
And I have to talk them off the ledge.
I tell them, “Criminals are pretty stupid, and they probably don’t know the value of your fish. And they certainly don’t have the patience to catch them!”
If you’ve ever tried to catch a fish, you know what I mean.
It’s probably a mink.
And sure enough, we’ll get another call from the neighboring house.
If we put all those calls on a map, we’d probably be able to track the mink moving around.
The unfortunate thing about mink is that they’re transient.
A heron has a great memory and may come back to the same pond repeatedly.
A mink just keeps moving.
Unfortunately, there’s not a lot you can do about them.
There are professional trappers who are licensed to trap them. We’ve hired mink trappers in certain situations and had some success, but not enough that I’d say it’s a guaranteed solution.
Bald Eagles
Bald eagles are another issue.
If a bald eagle dives down and grabs a fish, most of the remedies I’m going to talk about won’t work.
We actually installed this telephone pole behind me so that, if necessary, we could stretch cables from the pole to the building.
That’s the only thing we’ve found that can reliably prevent a bald eagle from diving into a pond.
We’ve done it in certain situations.
We had a couple of customers with beautiful ponds overlooking the river, and a bald eagle was coming every day and grabbing a fish.
We eventually installed a cabling system over the pond, and it stopped the problem.
Heron Deterrents
Let’s talk about what we can stop: herons.
They’re probably the most common pond predator.
Anybody know what this device is?
It’s a water squirter. We call it a ScareCrow.
Your garden hose connects to it, and you put a 9-volt battery in the bottom.
This is a motion sensor.
When it senses movement, it sends out a sharp stream of water.
It hits the bird, and the bird can’t figure out what’s happening.
It flies up to the corner of your roof and looks hungrily at your pond.
It’s thinking, “Okay, what just happened?”
Then it comes back down and gets blasted with water again.
After two or three times, it usually gives up.
We’ve found this to be very effective against herons.
It won’t work against mink, and it won’t work against bald eagles, but it works very well against herons.
The downside is that you need access to a garden hose, and you have to winterize it.
Floating Alligator
You’re going to laugh at this next one.
It’s a floating alligator.
You put it in the pond and weight it down.
The idea is that a heron won’t get close enough to see whether it’s real.
All the herons around here migrate, so they’ve probably seen alligators before.
They’ve come all the way from Pennsylvania to Florida, so they’re probably thinking, “Get away from home!”
But we’ve found it can be surprisingly effective.
Another thing we don’t sell—but probably should—is rubber snakes.
A decent-sized rubber snake sitting on a rock next to the pond can also deter birds.
Fake Herons Don’t Work
The device I don’t have out here is actually our number-one seller: the fake heron decoy.
They don’t work.
It’s our number-one seller, but they don’t work.
People like the way they look.
I could show you picture after picture of fake herons standing next to real herons.
Fake owls are the same way.
People will put a fake owl next to a pond, and then you’ll see a real heron standing right next to it.
The theory is that herons are territorial.
The idea is that if one heron is already there, another heron will think, “I’ll go find another pond.”
That’s not how nature works.
If a heron is hungry enough, it’s coming into the pond.
We’ve had customers say, “It worked!”
Until it didn’t.
So I can’t recommend fake herons as a reliable deterrent.
Fishing Line and Pond Nets
Someone asked about putting fishing line around the perimeter of the pond.
We actually have a wildlife-camera video on our YouTube channel showing a heron landing next to a pond.
It starts walking toward the water and encounters fishing line.
It steps over the line, grabs the fish, and doesn’t even look down.
Then it walks backward, lifts its leg back over the line, and walks away.
So I’m convinced fishing line isn’t very effective.
Some people also keep nets over their ponds.
The worst thing I’ve seen happen with that is a heron trying to chew or rip through the net to get a fish.
I’ve seen birds fly away with netting wrapped around their heads or ankles, get stuck in trees, and die.
Then the fish dies, the bird dies, and you have a net hanging in a tree.
I’m not a fan of that approach.
That said, we do have customers for whom a net is the only thing that works.
Fish Spawning
If fish are happy, they want to make babies.
If you have all goldfish in an ecosystem pond with plants, you’ll probably notice the goldfish spawning.
They might lay 100,000 eggs, and you may end up with five or ten babies.
That’s a pretty typical experience.
Then five years later you’re saying, “I’ve got to get rid of all these fish!”
And I’m saying, “No, you just need to make your pond bigger!”
The natural sequence of things is that environmental changes—like going from cold weather to warm weather—can trigger spawning.
In my personal pond, we’ve probably had two or three different spawning events in the past month.
It happens several times a year.
But I might only notice two or three babies every couple of years.
That’s because the fish eat their own eggs.
If you have all goldfish, you’ll get goldfish babies.
If you have goldfish and koi together, it’s much less common to get koi babies.
It’s basically a numbers game.
The goldfish—and everybody else—eat the eggs.
If you want to encourage baby fish, habitat plants can help.
Parrot’s feather is an awesome habitat plant because eggs can get caught in the foliage.
Bog bean is another great habitat plant.
Creating lots of little nooks and crannies in the pond gives baby fish places to hide.
I also have shallow beach areas in my personal pond that are heavily planted.
They’re only about a foot deep near the skimmer, so fish can’t get into all those little spaces.
That’s a great place for eggs and babies to hide.
Spawning usually happens in the spring, particularly when there’s an environmental change from winter into spring.
A lot of customers also report that when they take a fish home from our tanks, they get babies within two or three weeks.
That’s because moving the fish creates an environmental change.
If you keep your pond too clean, there aren’t any nooks and crannies for the eggs to hide.
Every time an egg appears, the fish are going to find it and eat it.
So there are a lot of factors involved.
A tiny pond is probably less likely to produce a large number of surviving babies than a larger pond.
But it’s nature.
Anything can happen.
And Barry Manilow. Who knows?
Winter Pond Care
We talked a little bit about winterization and what happens during the winter.
We sell a lot of pond heaters, but I recommend aeration over a heater, or at least aeration in addition to a heater.
A heater by itself doesn’t disturb the surface of the water.
When you put in an aerator or run a waterfall, you’re disturbing the surface.
That allows gases to escape.
Water molecules naturally want to stick together, so if nothing is physically moving the surface, gases can remain trapped.
A heater isn’t bad. It’s just not doing the job as effectively by itself.
Winter can be tough.
More and more people are choosing to shut down their waterfalls in winter and simply use an aerator.
It’s simple, and you don’t have to worry about pumps and plumbing lines freezing.
All of the ponds you see around here run exactly the same way all winter long.
We’ve designed them with the right parameters so we’ve worked out the kinks in the system.
Snails
Does anybody have any questions about fish?
Snails?
I don’t know why anybody would ever put a snail in their pond!
That’s my orientation.
No, snails are cool.
I like all kinds of wildlife.
There’s nothing better than watching a bunch of little kids crawling around my pond at home looking for snails and frogs.
When my kids were growing up, every birthday party involved finding snails, frogs, and all kinds of wildlife.
That’s awesome.
But I don’t recommend adding snails to your pond if they aren’t already there.
I’ve seen too many situations where snails colonize a pond and completely take over.
They can even get into a pump intake and damage the pump.
So snails are kind of cool, but I don’t want them destroying my pump.
If they’re already in your pond, I wouldn’t do anything drastic to get rid of them.
Just keep an eye on your pump and make sure they’re not colonizing the intake.
Plants and Nutrient Control
The bottom line is that when we talk about nitrates and removing nutrients, we’re also talking about reducing string algae.
String algae doesn’t care which nutrient is available.
For example, this particular plant needs a certain nutrient to produce that beautiful pink color.
Another nutrient produces the shape of the leaf.
This society garlic smells like garlic when you break the stem.
That’s another nutrient being removed from the pond.
The purple flower, the white stripe on the leaf, all of those characteristics are using different nutrients.
String algae doesn’t care.
So if we want to reduce stringy, fuzzy algae, let’s put a variety of plants in the pond.
Something tall.
Something short.
A round leaf will consume different nutrients than an iris leaf or an Acorus leaf.
This spike rush will consume different nutrients than the blood dock.
Look at all the different nutrients this plant needs just to grow.
The key to reducing string algae is to starve it by putting other plants into the pond that consume those nutrients.
Does that make sense?
People often ask, “What kind of plants should I put in my pond?”
My answer is:
Put them all in!
Once you understand that plants are part of your filtration system, the next question becomes: What looks good?
If you ask me to help design plants for a pond, I’ll go over to the plant tables and start grabbing different plants.
We’ll group them together and see what looks good.
We’ll look for different colors, textures, heights, bloom times, and other characteristics.
Maybe these three look good together.
We’ve got different variegated colors and textures.
It looks good to us, but it’s also doing a job of filtration.
It’s removing nitrates.
Choosing Pond Plants
This is a marsh marigold.
It’s one of the first plants to bloom in the pond.
It blooms early in the season, so I love having it because it’s pulling out those early-season nutrients.
You could pair it with something like purple cardinal flower.
One may be finishing for the season while the other is just starting.
That red-to-green contrast looks great.
But think about the nutrients being removed by the red leaves versus the green leaves, or the yellow flower versus the cardinal flower.
So how many plants should you put in your pond?
Pretty much put them in until you can’t see the fish anymore!
Aggressive Pond Plants
There are aggressive plants, though.
Somebody asked about plants taking over.
We built a pond up in Boiling Springs.
It was a gorgeous half-acre clay-lined pond.
Most of our ponds are lined with rubber liner, but this was a half-acre clay-lined pond on a 10-acre property.
The owners wanted native plants.
We brought in an expert on native meadows and did a huge amount of research to make sure we planted native plant communities.
We planted around 150 different varieties of native plants around that pond.
I told them:
Never, ever, ever put lotus in this pond. And never put cattails in this pond.
Two years later, guess what they did?
Cattails.
Within three years, the cattails had taken over the entire community around the pond.
All the work we’d done to create all these native plant communities was being overwhelmed.
We had planted hundreds of individual plants in groups to see which ones would outcompete each other.
It was going to look great.
The cattails won.
Eventually we restored the pond and removed the cattails.
It took three years.
We literally had to go in and paint each cattail leaf with herbicide to kill the cattails without destroying the remaining plants.
They did the same thing with lotus.
Lotus took over the pond, too.
So you have to be careful.
Acorus, for example, is an awesome plant for a medium-sized pond.
But if you put it in a very small pond, it could take over.
In a large pond, it’s a great plant.
It has that cattail-type appearance without being quite as aggressive.
You’ll notice we don’t have regular cattails on our plant tables.
We have miniature and dwarf varieties instead.
For most of the plants on our tables, the tags will tell you whether they’re appropriate for a small, medium, or large pond and whether they’re aggressive growers or well behaved.
The same goes for water lilies.
For the most part, if you’re grouping plants together—three plants in a group—you’ll find that’s a pretty effective way to keep everything under control.
You don’t end up with a monoculture of one plant.
Understanding Plant Tags
If you look at our plant tags, you’ll see a picture of the plant and a QR code.
Everybody knows what a QR code is.
If you point your iPhone at it, it’ll take you to our website.
Some plants have videos there, while others just have additional information.
The tag will also tell you the planting depth.
All of the plants on our tables will grow in your pond.
Some can grow in just two inches of water.
Others can grow a foot or even three feet deep.
The tag will tell you the appropriate depth.
And again, variety is best.
Plant some shallow-water plants.
Plant some deeper-water plants.
Plant some lilies.
Create variety.
Winterizing Pond Plants
What about winter with the plants?
Back in the 1970s, Better Homes and Gardens published an article saying you had to raise and lower your lilies.
If you look at my ponds, my lilies are planted in plant pockets.
I’ve never raised or lowered them.
They’re hardy plants.
If they’re hardy to this area, they’ll come back.
If you look at our plant tables, you’ll see that our hardy plants have a blue color code.
Tropical plants have an orange color code.
Tropical simply means they won’t survive below 32 degrees.
You treat them as annuals or replace them each year.
If it has a blue tag, it’ll come back year after year.
You don’t have to worry about raising or lowering it.
Planting Directly in the Pond
As far as repotting plants, we actually eliminate the pots in most of our ponds.
We’ll create a little plant pocket—an indentation in the rubber liner.
Then we’ll remove the plant completely from the pot and plant it directly into the pond.
Here’s an example.
This plant has completely outgrown its pot.
This is the best little soil knife ever.
It’ll cut through pots and roots.
You can use it to divide plants and make new ones.
Dividing Water Lilies
Here’s a third-year lily.
Most of the lilies in our tanks are second-year lilies.
We plant them out, let them grow for a year, and then by the third year they’re ready to divide.
You can see several places where new leaves are emerging.
We’ve got one, two, three, four, five growing points.
I could potentially divide this into five individual lilies.
First, rinse the soil off.
You need to be a little more gentle with the lily than with something like the cattail we were working with earlier.
Once you’ve rinsed all the soil away, you’ll find this hard tuber-like rhizome.
I’m going to carefully trim a piece of it off.
I’m cutting right between these two crowns.
There you go.
That’s a brand-new lily that I can repot and grow out.
I have one main growing crown here and two others here.
This is a great way to rejuvenate your lilies.
If you keep your lilies in pots, our potting soil is a nice organic mix.
Put the rhizome back in the pot, surround it with soil, and add fertilizer tablets to keep it growing.
If your lilies are planted directly in the pond and growing underneath the gravel, the rhizome will spread.
All you have to do is reach underneath the gravel with your soil knife and cut it back.
That allows you to keep the lily contained to the size you want.
When we build ponds now, we often make a tiny shelf specifically for a lily.
It can grow wherever it wants within that shelf, but it doesn’t really extend beyond it.
Water Lily Planting Depth
For water lilies, I always say 16 inches is the perfect depth.
They’ll grow at 12 inches.
They’ll grow at 24 inches.
But 16 inches is really ideal.
If you plant this lily today and the water level is here, this leaf will reach the surface in about two days.
If it’s planted 24 inches deep, it’s going to take more energy to reach the surface.
At 12 inches, it’s a little shallow.
Sixteen inches is really the sweet spot.
If you want to keep the lily in a pot, you can cut the rim off to make the pot more low-profile.
Then put a few small rocks around it and essentially create your own plant pocket.
But if your pond is crystal clear, who wants to look at pots?
That’s the thing.
We do have a lot of customers who keep their plants in pots.
Every year, they’ll bring the plants to us, we’ll divide them, and they’ll replant them.
Then they have extra plants they can give to friends.
So people do it both ways.
Planting the Biofilter
The question is: How do you plant the biofilter?
Our medium and large biofilters actually have a plant tray on top.
You can remove the plant from its pot, place it directly into the tray, and cover it with rock and gravel.
That does a great job of hiding the edge of the biofilter.
You don’t see it at all.
Even in the biofilter, I recommend taking the plants out of their pots.
The roots have better access to the water flow.
If you look at our small pond, you’ll see forget-me-nots growing in there.
Look at the roots on this plant.
They’re already growing out of the bottom.
You can see how fibrous they are.
We plant them right into the top of the biofilter, and those roots grow right down into it.
They’re great at removing nitrates.
Once a year, we’ll go in and pull the plant out.
With this type of root system, it’s not too difficult.
The roots tear pretty easily.
Some plants are more aggressive.
For a larger pond, buttonbush is a great shrub.
You can plant it in about a foot and a half of water.
It’s a great option.
Cypress trees are another awesome option if you want to add a tree to the corner of a pond.
When Should You Cut Pond Plants Back?
When do we cut the plants back?
In my pond, I like things a little messy in the winter.
I like the winter interest.
My pond has snow and ice on it, but the brown leaves of my Thalia are still sticking up.
Birds tend to use that vegetation during the winter, too.
Then in the spring, I’ll clean everything up.
Most of our customers are the opposite.
They want everything cleaned up in the fall.
They want the leaf net off, the leaves cleaned up, and everything cut back.
When you cut plants back, look at the water level.
You want the remaining stems to sit just above the water.
So if the water level is here, I’ll cut the plants back to just above the water.
These tips should remain above the water.
By the time the leaf net goes up, tropical plants have usually turned to mush anyway.
They’re tropical plants, so they’ll break down pretty quickly.
So let’s get those out of the pond.
That’s a great time to do it.
Some people like to wait until it’s still somewhat warm because we’re putting the nets up in September.
But two weeks after putting the net up, they’re usually saying, “Yeah, you were right. We should have taken them out!”