PlanetCatfish.com

I just set up one of my fish tanks. I used Bio-Spira to cycle the tank. I read around the Internet that it suppose to cycle a tank within a few days or within hours. I did some research and the people in the message boards said it works, the Bio-Spira. I do not know why mine did not work. My ammonia is very high. My Asian Redtails are developing fin rot and one has his eye all cloudy because of the bad water conditions. I put an antiboitic in there. I was wondering what will help me to cylce the tank. I had it for a week.

I would do a partial water change to bring the ammonia level down immediately.

What sounds worrying is that after the Ammonia spike there will be a Nitrite spike.

and add some peat!
it lowers the pH, wich causes ammonia levels to drop. but go gently on this one. It also inhibits bacterial growth, wich is benificial to fish already suffering bacterial diseases (like finrot).

And do as Siluris suggests; and keep it up; do waterchanges as often as possible.

Use a polyfilter of some description to remove the antibiotics, they will only kill more filter bacteria. I take it the fish never got returned to the lfs then.

Active carbon will work better to remove the antibiotics.

I did not return them. I know the catfishes will get big if I feed them. I like big fishes such as Pacus. I kept Pacus before then I returned them to the store when they got too big.