It's great to hear that someone is actually setting up a Q system. I caution you that a "crappy" bio-filter may not cut it. I suggest you place a high priority on having a reliable bio-filter, you can even use a spong filter with an air-pump. Myself I use a pump that pumps water above my container into a 5g salt bucket that I made into a wet-dry filter. I used pvc fittings and a rubber gasket to rig a drain in the bottom that drains via pvc back to my containter. I also rigged a drip tray on top by using a plant pot water drip tray, drilled it with lots of holes and was ready. I seeded it with bio-balls from my main system and let it go. I suggest you keep a cheap fish like a damsel or anemone in there until you add the fish you plan to keep. Plan to gradually feed these occupants a good amount so that they provide waste for your bio-filter to consume. Be careful not too much at first. If you do not plan to keep anything in the Q tank just add some flake food a couple times a week and that will feed your bio-filter, tho I prefer to have real fish waste being generated. You could even add more than one fish/damsels at first to get your bio-filter ready/adapted to a heavier bio-load. Then you can put (in a 10g) more than 1 fish in Q to eventually put in your display system. The idea is to exchange the bio-load (the damsels) for the new addtions keeping the bio-load on your filtyer the same. Another point is do not put any substrate, rocks or any calcium based materials in the Q tank. (glass, plastic or rubber only) Use large PVC fittings for hiding places.
Again I cannot stress enough the importance and often ignored value of your bio-filter. Water quality is most important when adapting a new fish to captivity. Good luck, Joe.
