I'm three weeks and two weeks respectively into doing a fishless cycle on two wet sump systems (each totals about 95 gals) with RO/DI these systems are using K1 media and biohome ultra as well as usual mechanical first stages. Dosed with 1 and/or 2ppm ammonia (Roundys brand if anyone is looking for pure). Ammonia has gone to zero a couple times over couple days in both systems. Have seen both nirites and nirates. There is a strong bio film because the K1 in the moving bed portion of the sump is now fully in motion. Also the above test results. Anyway, now I seem stuck. at 0.5ppm ammonia and 0.25 ammonia for days on end now. Been doing partial water changes all along from RODI adding trace minerals back in accordingly too. pH has been rock stable high 7's low 8's. Do I re-dose the ammonia? Or try another path? Or just wait it out?
Tank 1 has been in the 0.5 to 0.25 range for ammonia for over a week. Nitrites at 5ppm, Nitrates only thing moving is climbing, up to 40ppm now. So colony is cooking.
Tank 2 has been in similar ammonia range, nirites bouncing between 0 and 0.25ppm nitrate hanging at 5ppm. So again considering water changes daily things are cooking.
So any thoughts would be appreciated.
Tank 1 has been in the 0.5 to 0.25 range for ammonia for over a week. Nitrites at 5ppm, Nitrates only thing moving is climbing, up to 40ppm now. So colony is cooking.
Tank 2 has been in similar ammonia range, nirites bouncing between 0 and 0.25ppm nitrate hanging at 5ppm. So again considering water changes daily things are cooking.
So any thoughts would be appreciated.
and desire to automate top off and water changes without having to worry about chloramines etc. 
