Do they sell heaters for.......

[Alienbetta1]

....1 gallon tanks?

[doggyhog]

For a 1g tank a tetra 2-15 heater works well...

A 1g shouldn't really be a permanent home though... IMO it's just a little too small.

[secuono]

I think bare minimum for a Betta should be 3 gallons. Though I refuse to house any of my fish in less than 5 gallons. Recently, I had divided a 10 gallon tank 4 ways. Once I removed the 2 extra fish and gave the 2 residence their home(5gal) back, they were so happy and swimming all over. They really do use every square inch of space you give them.
^.^

[Alienbetta1]

Well I bought a heater for my tank and thanks!