phosphoric acid toxic to aquarium fish?

Question

Dose phosphoric acid toxic to aquarium fish, such as goldfishes and discus?

Answer 1

In large doses, yes. If you are using it to adjust the pH it's not enough to hurt the fish. I would point out that you are adding phosphorus to the tank which will cause additional algae growth so you might want to find another solution to the pH adjustment situation.

Answer 2

Like the cat above said... in large doses it can be toxic. I think it may be an ingredient in seachem's properPH line of products.

You should try and keep phosphates like this to below 1.5 ppm or else you're going to have a VERY bad hair algae problem. The worst kinds of algae thrive on elevated phosphate levels.

I lower my ph by adding DIY co2. Depending on your KH, you can drop the ph up to 1.5 points with co2 injection, and it makes the plants grow & bubble like crazy.

Answer 3

Yes, in two ways. First that an overdose it is toxic. Second is that a fast ph crash can kill fish (especially goldfish). Don't try adjusting your ph with chemicals.