The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.
Can you use any brand for your planted tank? Are there any common ingredients or brands that should be avoided? I am thinking about buying some for my planted tank.
Amaco pottery clay is what a lot of people use. It's air drying so just leave it out for 24 houses then crush is in to a powder. I read somewhere 1/4 lb per square meter. I just guessed and chucked a healthy looking slab in.
Clay is good for cation exchange as well as iron. It's a must IMO.