Mebbid
Aquarium Advice Addict
Where did the gravel come from? Could it be possible that there was a chemical on the gravel that would kill the BB in the tank? Are you having any ammonia readings in your tap water?
Assuming there is no ammonia in the tap water than back to back large 50%+ water changes are the best way to lower the ammonia. Just leave the tank with 1 hour between water changes. Once you get it dropped to an acceptable level than it is easier to maintain.
Until you get the ammonia under control I would suggest dosing prime as a detoxifier and invest in some sort of ammonia removing chips. Assuming the ammonia isn't solely coming from the fish, the ammonia source will eventually wear itself out and go away.
Assuming there is no ammonia in the tap water than back to back large 50%+ water changes are the best way to lower the ammonia. Just leave the tank with 1 hour between water changes. Once you get it dropped to an acceptable level than it is easier to maintain.
Until you get the ammonia under control I would suggest dosing prime as a detoxifier and invest in some sort of ammonia removing chips. Assuming the ammonia isn't solely coming from the fish, the ammonia source will eventually wear itself out and go away.