Originally Posted by
lilzeus99
http:///forum/post/2753633
If you have an already cycled DT, can't you just use some of the water out of the DT durring a water change to fill the QT? Then you only need water in the QT when you have a fish in there? Thanks...
The water is not really what is "cycled". The filter, LR, substrate, or whatever holds the bacteria that act as your bio-filter is the main component of a cycled tank.. Water from an established tank is no more "cycled' than freshly mixed, new water. That's why I always suggest keeping an extra filter sponge in an active system. Bacteria will colonize the sponge and you then move the sponge, bacteria and all to the new tank. "cycled water" is a very common misconception and I'd suggest you read up on cycling so all this makes sense.
Using the water from a DT is fine, but that won't result in a "cycled tank". But, assuming you keep your DT water healthy, you will have water in your QT that is very similar in PH, SG, etc., to your DT. Also, it saves the mixing and saves a few bucks.