yhbae

I know live plants are helpful in aquariums. I have them in just about every aquarium I own. Never really thought of it much because it is a no-brainer unless species I keep eat them.

Since then, I started writing an online bioload calculator and tried to figure out what would be the effect of plants on the bioload. Many many people have been suggesting that I should add this "feature". Yes, plants do absorb _some_ toxic chemicals excreted by fishes, including ammonia and nitrates. On the other hand, I also read that fishes produce plenty more toxic chemicals/toxins that are not absorbed by plants.

So here's my ultimate question - can you keep more fishes in planted tanks? If so, WHY?

I always thought of having plants as a safety net rather than a mean to increase the total bioload of my tanks. But I would gladly stand corrected if this is not the case.

coffeebean

it really depends on how heavily planted it is. IMO very heavily planted tanks can handle a few more fish, i wouldnt push it too far though

Red1313

There's a really good book out by Diana Walstad called Ecology of the Planted Aquarium. It's a really neat read and explains alot about what plants do in an aquarium (even if you don't set up a tank by her method). Basically plants act as Water Purifiers in an aquarium. Which means your parameters stay stable longer. Which I suppose means you can allow a longer time between WC's or add a bit more plant friendly stock to the tank if WC's are maintained... However we're talking about planted tanks where there's more plant then visible substrate (underwater jungles if you well) and that can have problems itself.

mathas

As I said in another thread, "while planted tanks absolutely do allow a higher bioload than a non-planted tank, it's tricky to quantify just how much extra you can get away with. Different plants absorb nitrogen at different rates, and different fish produce different amounts of waste."

Can you add a couple of slow-growing plants to a 75g tank and suddenly be able to safely keep three adult oscars in it? Probably not.

Can you have a heavily planted 75g tank and add a few more cardinal tetras than you could have supported without the plants? Probably so.

edit: Note, though, that overstocking a tank has drawbacks other than pure bioload concerns. I think your attitude of treating plants as a safety net rather than a reason to overstock is the right attitude to take.

speed0factory

It can handle more fish i guess, but it also depending on the size of your fishes and your tank. Some fish needed more space then the other.