So instead of trying to find small enough heaters to heat my 1.5 and 1.77 gallon tanks, I decided to upgrade and buy a 5.5 gallon tank.
I bought a 25w Elite heater also and I'm currently testing it in the new tank.
I made my own divider in the tank (couldn't justify paying $15 for one)using plastic mesh so the water can circulate well. But if they can see each other through the mesh, will they get stressed out or eventually get used to it?
And when I put the fish in the new heated water should I heat up the water first and acclimate them or should I turn the heater down and turn up the temp. slowly with them in the water?
I'm always nervous when doing new things with my "fish babies" and I just need some reassurance that I won't hurt them.