Thats exactly what I did, which is take a mature filter cartridge and plop it into the sponge filter. That is what leads me to beleive the possible additives are killing off the bacteria.badflash wrote:You must have access to another tank with a filter in it don't you? Just remove the filter and cllean itout in the new tank. Presto! Cycled tank.
-John (AKA: The Puffer Ninja)