Have you checked the water going in after the water change as it sounds like you have nitrate in the tap water. You can use a nitrogen or nitraghost on that if this is the case although you cannot run too high pressure through them and they need to be recharged every few hundred gallons.IrnGynt;4796487; said:Why couldn't I have found this thread a year ago???
Anyways, I'm going to give this a shot. I've been battling high nitrates in my 75g since inception. One big cichlid (Flowerhorn) with weekly 50% water changes and I still can't get the nitrates below 20ppm.
I'm envisioning a decorative window planter on a shelf over the tank which the sump feeds into. Two overflows which feed back into the tank and as many Pothos suspended above the water as it takes.