Problems with Algone!

Btw what's activated carbon?
This should answer your question.
http://en.wikipedia.org/wiki/Activated_carbon

It is used to remove stains, odors, tannic acids, medicines and other chemicals added in the tank. It is readily available in pet stores and should be replaced after using for almost four weeks. I don't recommend the use of carbon unless you intend to remove something from your tank.
 
Has the tank cycled? Once the tank is cycled properly, you should not have an issue with Ammonia and NitrItes and water changes should be used to keep your NitrAtes down to a reasonable level. If you are having issues with high NitrAtes, you may be over loaded or over feeding. If the Ammonia or NitrItes are high, you may still be cycling the tank.
 
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