I put together a fish only 36 gallon tank about 2 months ago. It has a heater (set at 80degrees), a hang on back filter thats good for up to 50gallons. I used live sand and some Seachem tank stabilizer to kick start it, and I added a Blue Damsel in a month after that...All the levels were at 0. Waited a week to see how the Blue Damsel did, and then when he was ok, added 2 false percula clown fish. Waited a few more days and added a little Yellow Tang and Royal Gramma.
I noticed a little white spot on the yellow tang that day, ICH, so I went back down to the LFS
and got some copper, since its a fish only tank, shouldnt have much problems, right? Well a few days later the Yellow tang died, and all my fish have the white spots on them. I keep using the copper, but it doesnt seem to be doing anything yet. I also bought a UV
I noticed my clowns gasping on the surface, so I do some water testing.
Nitrite is ridiculously high. Couldnt tell if it was 5.0ppm or 1.0ppm, because the colors were too close. Also the ammonia levels were high (.50ppm). I did a 50% water change, and the nitrate went down to .50ppm. Ammonia stayed the same. I put in some Ammo-lock to detoxify the ammonia.
Nitrate was at ~10ppm before the water change. Anyways, when I woke up the next morning, I tested the water again. The Nitrite was right back up to 1.0ppm....Did another 50% water change. Brought it back down to .50ppm. I have done that a few times, but it just goes right back to 1ppm within a day. I decided to do an 80% water change, and it brought it down to about .25ppm, but it still went back up to 1.0 the next morning. Then my royal Gramma died, and one of my clowns is on the verge of dying. I cut back on feeding them to only about 3 times a week to cut down waste/uneaten food. Also, there is brown slime all over my rocks, decorations and sand, is that normal? I have no idea what to do. I am going to end up starting all over, but my tank was cycled, I shouldnt have had this problem to begin with.
What happened? How can I fix this?