Dump your old carbon and go get this...

[DiverDude]

Somebody correct me if this isn't right but my understanding is that ROX is a more porous carbon and does a better job (per unit volume) of absorbing impurities than other forms of carbon.

That said, if you use a larger amount (and/or perhaps over a longer period of time) of an inferior grade of carbon, you should still be able to achieve the same results.

In other words, it's just more efficient.

[Milad]

the caco3reef stuff i think its a bit different, mine says .8 not 1.3. Might just be the size. The .8 is really really really small, you need a BRS reactor or something similar.

I was filling the BRS reactor with the kent carbon and I followed the instructions for this ROX and only put 1.5 cups of it into the reactor. I probably put about 6 cups of the other carbon into the BRS reactor so it must be much more efficient.