Hello, We have a female beta in a 2.5 gallon tank with a filter and a heater that keeps it between 73 and 76 degrees, usually. She was doing really well for about 4 months or so, swimming around/coming out to eat, etc., and then she started to show signs of stress--she was darting around...

Hello again! So I'm soon going to be full-out cleaning my betta's tanks soon. My bettas are each in a 2.5 gallon tank and i was wondering if i would need a gravel cleaner. It'll be my first time cleaning any type of fish tank so any advice really would be much appreciated! Thanks :-D Edit...