I would like some info on whether it is possible to put a 50 watt heater in a one gallon container. Most small heaters say "from 5 to 10 gallons". I have put myself in a situation where I have to keep a small container warm enough for a betta on a temporary basis. My sense says if has a thermostat, it should shut off when it reaches the set temp no matter how much water it is in.