I have a 125 gallon freshwater tank that we cycled with roseys (we now know about fishless cycling but a local pet store advised us to do it this way) and we saw a spike in nitrites and then low ammonia levels. We added our fish a couple every week or so and all was well for a few weeks. Then the fish got ich. We dealt with that but lost a few fish. Now we have 2 tiger oscars, 2 electric blue jack dempseys, 2 bala sharks and a pleco. All are juveniles around 2" - 2 1/2". After the ich problem, during a routine water change I cleaned the filtration system with tap water which I now know killed all the beneficial bacteria. We had what I'm assuming was a bacterial bloom because the water was cloudy for a couple days then cleared up. Since then, the ammonia has been off the charts for over a week and we can't seem to get it under control. We have tried a couple different things including Ammo Lock and daily water changes up to 25% per day with heavy gravel vacuuming but the ammonia is still high. According to API ammonia test kit, dark green is 8.0 ppm and our tests get dark green after a couple minutes.
So I guess my question is, is the tank re-cycling? And if it is, how long should it take and what should we do? Could it be lack of filtration? We have a Rena Filstar xP3 that is rated at 175g and 350 gph of flow. It's set up like this: bottom tray - 20ppi and 30ppi foams, middle tray - bio-chem stars, top tray - RENA crystals, ZeoLite ammonia remover and micro filtration pad. Should we add another xP3 to our aquarium?
Both my wife and I are fairly new to aquariums, we both had smaller ones when we were kids but that's about it. Any help you could offer would be appreciated!! I tried to include everything I could think of but let me know if you need any more info. Thanks!
Update: I just tested for nitrites and it's high too, around between 3.0 and 5.0 ppm. Our fish seem to be stressed too, picking on each other so any help would be appreciated. Thanks!