[shark]

I still agreed with Tay suggestion.. the best way to remove nitrate or ammonia is do regular WC on a regular basis and change the filtering wool weekly or bi-weekly.. all the chemical or mechanical filter will not help in long run, it might be worst if the filter breakdown, such as pump stop, oxygen level drop etc etc.

oso.. control your feeding to the fish.. excess food will cause water to go bad very fast.

and be patience... reducing nitrate or ammonia is not a over night thing.. it take time to make thing change from bad to good... patience is the key all all fish keep success.

too fast water parameter changes is also no good for the fishes or BB inside.