I have had a 30 gallon tall sitting around and decided to put two female bettas in it. They are super tiny, both about an inch. I have no filter and do not plan on putting one in the tank, because I think it will be too much for them. I have an air pump in the tank and I think it produces to much current at the top sloshing the poor things around oh and of course i have a heater.
My question is since they are the only two in the tank and with no filter how often should I change the water? Will the bacteria ever grow or will I be changing the water too much for it to grow? And for the air pump if I buy an airstone and connect it to the pump will it produce less current?