For corals, I use a 10g bare bottom tank, Duetto Submersible filter, heater and a frag shelf. It's lit by a Kessil that I can dial up or down. I don't treat the QT, but rather dip the corals before they go in to the QT. I like Revive, Flatworm Exit and Interceptor, though I've used other products as dips with good success. After dipping and rinsing the corals, they go into the QT for a few days. I dip a second time and once in a while a third, looking for nudis and eggs or other nasty critters, depending on the type of coral. A liberal application of a small brush for removing unwanted hitchhikers is used. I somehow manage to miss the inevitable aptasia... just ask Daniel (AquaticArt) about my recent Peppermint Shrimp acquisitions!
If I'm adding inverts to the fish displays, then I usually QT them for a couple of weeks... while the shrimp or snails themselves aren't susceptible to nasties, the water that they are in can carry free swimming parasites. Flatworms can often be found on snails and crabs.
I maintain water quality in the frag tank by changing water from the display and into the frag tank. It serves two purposes... increases the frequency of water changes on the display and acclimates the corals to my system.
Do I QT everything with equal diligence? I must admit, no. It depends on where the animal came from and into which tank it is heading. If it's going with the seahorses, I'm a little more lenient. If it's going into my 175 fish display, it may spend 6 months in QT.
