Dick wrote:
On Wed, 22 Jun 2005 08:57:46 -0400, Steve wrote:
Activated carbon filtration mainly removes dissolved organic carbons
(D.O.C.). The D.O.C. gives the water a brownish tint, which the carbon
removes nicely.
Steve


Interesting. One problem I have avoided somehow. Where does the
D.O.C, come from? Dead vegetation, particular foods, or what? My 5
tanks have never shown a brownish tint. Is it a common problem?

dick
Try using a white 5-gal pail for water changes, and you'll probably see
the brownish tint in your aquarium water. You may possibly see colour in
your tap water too, which is why they sell activated carbon filters for
drinking water (removes taste, odour, colour).
Steve