He is Jackson, and he came white with a small amount of blue... Now he is white and blue xD
The "half gallon" you mentioned is actually a 2 gallon (measured). I had to use a heater, in the heated room, because that poor little lady had ich. So I killed it off with AQ salt and 85 degrees
She didn't mind.
I think that heater is meant for 5-10 gallons, but I adjusted it by a degree at a time until it heated it just right. It heats it faster than it would heat a 10 gallon, obviously. I found it sucks for 10 gallons... It is one of the ones from ebay.
For any half gallon tanks, it is pretty hard to find heaters. Unless you can find a 7.5-10 watt heater, which I dislike any preset ones. I use 25 watts usually for smaller quarantines, if needed. Otherwise it is a heated room or summer time