So now that I am getting ready to stock my tank, I'm now looking at setting up my QT. This is what I'm thinking, please let me know if you see anything amiss. I have a 5 gallon tank that I had a betta in. His tank was cycled, but he died by choking on a pellet. The tank had a DIY filter I made. I still plan on giving the tank to my mom for her to have a betta, and I plan on picking up a 10 gal at petco to use as QT. I have added a submersible filter to seed for my mom, and am keeping it cycled with ammonia. So giving to mom: 5 gallon tank Submersible filter Tetra heater 5-15 gal, auto set Using as my QT 10 gal DIY filter Aqueon heater, 50 watt adjustable Since this is planned to be a QT for new fish, I'm going to have a simple substrate and a couple fake plants for hiding places. Should I just use sand? I find it easier to clean and see debris.