Just a trickle filter is enough. You can get a sponge( just a regular sponge) from your LFS
and seed it with nitrifying bacteria from your main. Place it in your sump or filter in you main for a week or 2 and transfer it to the qt
tank filter. That along with water from you main, and you have a ready to go qt
Just don't get a sponge from the grocery store or something. Those are sometimes treated with chemicals that you don't want .