All the QT tank needs in it is water. Most QT tanks are kept bare bottomed in order to keep it clean easier. Also keeping it bare bottomed allows you to see just how much your fish is eating. Food goes in poo comes out. No poo means he's not eating.
Theres more to cycling a filter than just running it. There has to be a source of ammonia or the beneficial bacteria will never grow. Cycle time varies but usually your looking at about a month before fish can be added. Read this guide to fishless cycling.
Fishless Cycling - Everything You Wanted to know... It's geared towards fresh water but the same principle applies to salt water.
It's recommended to break down your QT tank when not in use to help prevent you from being tempted to put fish in it and make it a second full time aquarium. Really no need to worry about nasties growing in the filter. It's just the nature of the beast to want to keep more fish. MTS eventually gets us all.
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