I am in the process of cleaning a 90 gallon "lack of maintenence" aquarium. This tank is SO SKANKED!! Everything I dissasemble to clean has a HUGE amount of thick brown sludge adheared to it. Is this sludge the nitrate bacteria that breaks down ammonia? My last question is I have a 5 gallon pail about 1/2 full with gravel and sand and water. Should I use this gravel in my new setup, or is this not a good idea? Thanks,
Rich
Rich