I know most pet stores and pet store people who try to sell those little Betta bowls try to say Bettas do not need to have warm water, but they are tropical fish and don't do very well below about 74 degrees and like it better around 78 so I would fix it so it doesn't ever go below 74 and over 80 unless they need medication. When they need medication the medications usually require a raise in temperature to at least 82 degrees to have maximum effect. If the problem is
ICH sometimes all that is needed is to raise the temperature to 85 for a week to ten days or so as it is definitely a "cold water" disease and the parasite will not let go of your fish in cold water. It goes free swimming in warm water of 85 degrees and then will die if the water is left that warm for at least a week but ten days is better.
I got some of my information from Butterfly and Gunnie and some from a fish vet I know as well as the people at Aquarium Pharmaceuticals who I will have to say were nice enough to give me the tip about raising the water temp for ich and didn't just try to sell their product, although they said I could use a product if I would feel better. There have also been several books on Bettas I have read and "The
manual of fish health" by Dr. Chris Andrews, Adrian Exell & Dr. Neville Carrington. They give a lot of general information but some of it related to Bettas specifically
I hope this has been helpful. I love my fish and so have tried to find out as much as I can to keep them happy as I am sure you are. If you find anything that I may find useful I will welcome the information.
Rose
