aquasoil and po4 absorbing


Lifetime Charter Member
Lifetime Member
Nov 30, 2005
I need help....

I replaced last week in part my substrate. I was unhappy with the perfomance of the inert substrate flourite dark. So I added to the flourite dark 30 liters of colombo flora base, which is an ada aquasoil imitation.

The question is as following: I add PO4 EI based, but after one day PO4 drops below 0.5 mg/l. After browsing the internet, I found that aquasoils can absorb PO4.

So the question is what to do???

increase PO4 dosage to maintain >1 mg/l PO4 or keep the normal EI style PO4 dosage which will give a very low watercolumn PO4 level.
Of course, if I add more PO4, the substrate will absorb more PO4 etc. is this a bad thing? will it release the po4 at some point?