The tank I'm so proud of lol...1 piece of malaysian driftwood [large], small rock, plants that are looking good, 10 danios, 1 flame gourami [will eventually add a blue neon i think]. 20 gallon tank/30 gallon filter.

My last question is....is a heater necessary?!? I gotta admit the water feels cold. will this seriously effect the fish? hard to imagine water anywhere staying warm overnight in nature.... If I gotta get the heater, any suggestions as to what I should get?

[I searched heater in the forum search bar but couldn't find anything pertinent, and I know you guys like to be kept busy =p ]

Thanks!