Ok, so the maxi-jets are fixed, eheim cleaned and the nitrates have at least leveled out. Skimmer seems to be slowing down but the ppm is not going below 50.
So now I'll try taking the bio wheel out but have a question first. I've seen how Otty set up his sump and the rock was out above the water level using the the light difuser.
My question is what is the advantage or reason for putting the rock above the water level in the sump? |