I was just reading yet another thread where there many posts saying the path to no algae is no nutrients. I didn't want to post there because it only upsets people. But for people wanting to know how ponds and algae really work I thought I'd post a few things people could check out for themselves.
For people who already have a pond I don't think these myths do any great harm. For people designing a pond these myths cause people to change plans like move from a sunny location where they'd like a pond to a shady location that is less desirable. Or increase cost and work by building "filters" that do nothing or add plants that can increase algae and make algae removable difficult.
Myth #1 - Sunlight causes algae so shade kills algae
It is true plants need sunlight. It's true a total lack of sun would eliminate algae. The myth is that algae can't grow in low light.
How much light do plants need? Well moss grows on the north side of trees. That's total shade. Plants grow on the ground in a rain forest. People who keep aquariums certainly know algae grows indoors with almost no light.
Consider a green pond in full sun...really bad right? Well most of the water is actually very shaded because the green water blocks light. In a green pond light barely gets down a couple of inches, yet if you brought some water up from the bottom it would be green. This includes ponds with no water movement.
Shade is actually better for algae. UV is harmful to algae. Algae can only use about 10% of full direct sunlight. So moving a pond because a bunch of people believe the myth and repeat it a million times can really work against you.
Myth #2 - Starving algae out of existence
By far the wackiest and most repeated "fact" in the pond world. There are two parts to this. Part one is many people seem to think plants use nutrients like we use food as a fuel. False. Like us nutrients are mainly used to build new cells. Algae create fuel via sunlight. They need virtually no nutrients to produce fuel. Unless you consider water and carbon as nutrients. Good luck removing water and carbon from your pond.
Part two is the belief somehow nutrients in a pond can be made low enough to eliminate algae growth (cell division). This is pure fantasy. Say you measure your pond water and find 0 nitrate and 0 ammonia. Pond is nutrient free right? Nope. Fish produce ammonia right? How can any pond be nutrient free if there are fish? To say nothing of the fish food we toss into the pond.
BTW, what is fish food? Mostly it dried fish, shrimp type stuff. Basically the same stuff in fish emulsion, a plant fertilizer.
Lots of people say their super duper filter removes nutrients and starve algae. No such pond filters exist. At best maybe a few might lower nitrate a bit but these are not common filters.
Algae eat ammonia.
Let's take the ammonia continuously coming off of your fish. Algae will consume ammonia directly as their primary nutrient for cell creation. Not only can they do it, they prefer it. Given a water sample with algae and ammonia and nitrate the ammonia will be consumed first. There's a chemical reason for this but lets just say ammonia is like candy and nitrate is like broccoli. Algae can consume both, but prefers ammonia.
So the idea is the fish produce ammonia which disperses evenly throughout the pond very fast. But for some reason algae will refuse to eat this candy and instead wait for all the water to go thru the super duper filter which removes the ammonia and starves the algae. That would be very nice of the algae wouldn't it? Wacky, wacky concept.
And what does this super duper filter do? Converts the ammonia into nitrate which the algae can also consume.
Then why is everyone talking about bio filters and the nitrogen cycle????
That all came from aquariums and later Koi Ponds. In those systems ammonia is a big problem. Koi Ponds (actual Koi Ponds, not just ponds with Koi) are kept very clean. They do all kinds of things to kill algae and keep it down. Plus they generally have very high fish loads. Water Gardens are much different systems. Low fish loads and generally a lot of algae. Even a clear Water Garden with little visible string algae will still have a lot of algae and other creatures. This is why most Water Gardens don't need the bio filters Koi Ponds need.
Plants
Or maybe add higher plants to the pond. Water hyacinth, that'll starve algae. Again, we're back to the same wacky idea. Why would algae starve while the WH thrive? There's plenty of nutrients for this huge complex plant but not enough for this single cell plant? It makes ridiculously little sense.
Actual data is steps away.
When people stop typing myths on keyboards and instead, get up, and actually measure the nutrient level in different ponds the myth is fully exposed. A green pond will almost always measure 0 ammonia and O or very low nitrate. A clear pond will almost always measure fairly high nitrate. The exact oppose of what the myth says. You can do the test yourself or read pretty much any study on algae in farm ponds, lakes, etc. Or just keep typing the same myth over and over which is even easier.
Less growth - no growth are 2 completely different concepts.
Less sunlight and nutrients can reduce growth but that is not the same thing we see in algae free ponds. If you reduce sun and/or nutrients you will get less algae. Your pond will still be green, but less green. Instead of the pond being completely full of string algae it might only be 1/2 full.
Almost algae free, which is what we're after, is another deal altogether. We know this because there are lots of ponds in full sun, lots of nutrients, and almost algae free. And because of experiments that show the solution.
The algae mystery explained.
If you saw a moose coming to your pond everyday and watch it munch string algae you would know why your pond is algae free. People make this same connection to filters, shade or whatever they do to remove algae. "I added X and 3 weeks later the algae was gone so obviously X works".
But there is more to your pond than what you can see. Look at the water under a microscope. There are an amazing amount of life in there. Animals, bacteria, virus, algae. It makes the African savanna or a rainforest look like a lifeless moon scape.
Algae live in this world. For green water algae this is their entire world. But even string algae starts out as a single cell. Why can't we even consider this world as a reason for why algae comes and goes? Because we can't see it with our naked eye? Is that really the limit of our ability to understand things? It was up until 400 years ago at least for many people.
The elephant in the room is zooplankton. Your pond is full of these algae eaters. These are well known, studied and taught about. Why do they get no credit? Because we can see them? Too bad we can read either.
This world is really complex and we're learning more everyday. But there is already a lot of research that shows there are epic battles fought between animals, plants and bacteria. We know for example that water from a clear pond (that naturally converted from green) is toxic to green water algae. If you pour water from the clear pond into a container of water from a green pond the algae will die very fast. The same for water being toxic to string algae.
We don't fully understand all the processes. But the first step is to leave myths behind and find real solutions.
TV show that explains a little of the latest research.
The TV show Nature did a great show last year called What Plants Talk About that might open a few minds to a more realistic understanding of ponds and algae. You can watch the entire show here. Thank you PBS.
If you're planning a pond or looking for an algae solution and think a bog, or plants are the solution good luck to you. The good news is that in most ponds algae will be killed by all these tiny creatures and plants and you can believe it was the bog, or filter, or plants.
For people who already have a pond I don't think these myths do any great harm. For people designing a pond these myths cause people to change plans like move from a sunny location where they'd like a pond to a shady location that is less desirable. Or increase cost and work by building "filters" that do nothing or add plants that can increase algae and make algae removable difficult.
Myth #1 - Sunlight causes algae so shade kills algae
It is true plants need sunlight. It's true a total lack of sun would eliminate algae. The myth is that algae can't grow in low light.
How much light do plants need? Well moss grows on the north side of trees. That's total shade. Plants grow on the ground in a rain forest. People who keep aquariums certainly know algae grows indoors with almost no light.
Consider a green pond in full sun...really bad right? Well most of the water is actually very shaded because the green water blocks light. In a green pond light barely gets down a couple of inches, yet if you brought some water up from the bottom it would be green. This includes ponds with no water movement.
Shade is actually better for algae. UV is harmful to algae. Algae can only use about 10% of full direct sunlight. So moving a pond because a bunch of people believe the myth and repeat it a million times can really work against you.
Myth #2 - Starving algae out of existence
By far the wackiest and most repeated "fact" in the pond world. There are two parts to this. Part one is many people seem to think plants use nutrients like we use food as a fuel. False. Like us nutrients are mainly used to build new cells. Algae create fuel via sunlight. They need virtually no nutrients to produce fuel. Unless you consider water and carbon as nutrients. Good luck removing water and carbon from your pond.
Part two is the belief somehow nutrients in a pond can be made low enough to eliminate algae growth (cell division). This is pure fantasy. Say you measure your pond water and find 0 nitrate and 0 ammonia. Pond is nutrient free right? Nope. Fish produce ammonia right? How can any pond be nutrient free if there are fish? To say nothing of the fish food we toss into the pond.
BTW, what is fish food? Mostly it dried fish, shrimp type stuff. Basically the same stuff in fish emulsion, a plant fertilizer.
Lots of people say their super duper filter removes nutrients and starve algae. No such pond filters exist. At best maybe a few might lower nitrate a bit but these are not common filters.
Algae eat ammonia.
Let's take the ammonia continuously coming off of your fish. Algae will consume ammonia directly as their primary nutrient for cell creation. Not only can they do it, they prefer it. Given a water sample with algae and ammonia and nitrate the ammonia will be consumed first. There's a chemical reason for this but lets just say ammonia is like candy and nitrate is like broccoli. Algae can consume both, but prefers ammonia.
So the idea is the fish produce ammonia which disperses evenly throughout the pond very fast. But for some reason algae will refuse to eat this candy and instead wait for all the water to go thru the super duper filter which removes the ammonia and starves the algae. That would be very nice of the algae wouldn't it? Wacky, wacky concept.
And what does this super duper filter do? Converts the ammonia into nitrate which the algae can also consume.
Then why is everyone talking about bio filters and the nitrogen cycle????
That all came from aquariums and later Koi Ponds. In those systems ammonia is a big problem. Koi Ponds (actual Koi Ponds, not just ponds with Koi) are kept very clean. They do all kinds of things to kill algae and keep it down. Plus they generally have very high fish loads. Water Gardens are much different systems. Low fish loads and generally a lot of algae. Even a clear Water Garden with little visible string algae will still have a lot of algae and other creatures. This is why most Water Gardens don't need the bio filters Koi Ponds need.
Plants
Or maybe add higher plants to the pond. Water hyacinth, that'll starve algae. Again, we're back to the same wacky idea. Why would algae starve while the WH thrive? There's plenty of nutrients for this huge complex plant but not enough for this single cell plant? It makes ridiculously little sense.
Actual data is steps away.
When people stop typing myths on keyboards and instead, get up, and actually measure the nutrient level in different ponds the myth is fully exposed. A green pond will almost always measure 0 ammonia and O or very low nitrate. A clear pond will almost always measure fairly high nitrate. The exact oppose of what the myth says. You can do the test yourself or read pretty much any study on algae in farm ponds, lakes, etc. Or just keep typing the same myth over and over which is even easier.
Less growth - no growth are 2 completely different concepts.
Less sunlight and nutrients can reduce growth but that is not the same thing we see in algae free ponds. If you reduce sun and/or nutrients you will get less algae. Your pond will still be green, but less green. Instead of the pond being completely full of string algae it might only be 1/2 full.
Almost algae free, which is what we're after, is another deal altogether. We know this because there are lots of ponds in full sun, lots of nutrients, and almost algae free. And because of experiments that show the solution.
The algae mystery explained.
If you saw a moose coming to your pond everyday and watch it munch string algae you would know why your pond is algae free. People make this same connection to filters, shade or whatever they do to remove algae. "I added X and 3 weeks later the algae was gone so obviously X works".
But there is more to your pond than what you can see. Look at the water under a microscope. There are an amazing amount of life in there. Animals, bacteria, virus, algae. It makes the African savanna or a rainforest look like a lifeless moon scape.
Algae live in this world. For green water algae this is their entire world. But even string algae starts out as a single cell. Why can't we even consider this world as a reason for why algae comes and goes? Because we can't see it with our naked eye? Is that really the limit of our ability to understand things? It was up until 400 years ago at least for many people.
The elephant in the room is zooplankton. Your pond is full of these algae eaters. These are well known, studied and taught about. Why do they get no credit? Because we can see them? Too bad we can read either.
This world is really complex and we're learning more everyday. But there is already a lot of research that shows there are epic battles fought between animals, plants and bacteria. We know for example that water from a clear pond (that naturally converted from green) is toxic to green water algae. If you pour water from the clear pond into a container of water from a green pond the algae will die very fast. The same for water being toxic to string algae.
We don't fully understand all the processes. But the first step is to leave myths behind and find real solutions.
TV show that explains a little of the latest research.
The TV show Nature did a great show last year called What Plants Talk About that might open a few minds to a more realistic understanding of ponds and algae. You can watch the entire show here. Thank you PBS.
If you're planning a pond or looking for an algae solution and think a bog, or plants are the solution good luck to you. The good news is that in most ponds algae will be killed by all these tiny creatures and plants and you can believe it was the bog, or filter, or plants.
