Hi everyone, my husband got excited and purchased my son a betta fish. We have had him for a week now and I have noticed he is darting around spazzing out and hiding behind the heater. Here is some tank information, he is in a 3 gallon tank with a filter that came with it and a heater. My question is, could the filter be to strong for him? I have Google and read different things. Some say filter can produce a strong current in small tanks. I turned it off and he is swimming around again. Is it alright to not have it on and just change his water 20% every 4 days? Until we purchase a bigger tank? Thank You!