On a new setup, I check ammonia, nitrite, nitrate, pH, temp, KH
, and GH
pretty regularly. Once it is full of plants, I will check several times after the first few doses to make sure I am getting the Fe
doses correct, and adjust accordingly.
Once the ferts are on track and the tank is established, I don't really test for anything (except continuously checking CO2
using a drop checker, and a PO4
test once every 6 weeks or so) unless I think something is wrong.