look, to be honest theres not an awful lot we can help you with if youre not willing to provide us with full details of whats happening here,
you havent said what filtration you have and you still havent said if you vac the gravel
changing 30% a week would be all and well and good if you just had the oscar in there ( but i always do more like 50%) just beacause your tests say the all is nearly ok, if all the crap is in the gravel,its like hidden dangers,
please posts pics of
the lump
the full tank
the filter
the test kit you use
no one is going to have a go at you, we want to help but at the moment we are still guessing the basics,,and have been for the last 3 days, the oscar could be well on the way to recovery by now, hes obviously suffering,so please come on help us to help you
shelagh xxx