Greetings everyone. I am a new betta fish owner and had a few questions I was hoping could be answered.
First of all I have two bettas. They both reside in 2 gallon fishbowls that I change weekly and add water conditioner to every couple days. I leave the bowls in the sunlight during the day and the water temp peaks at about 74 degrees during the day and drops to about 66-68 degrees during the night. Is this an acceptable betta climate, or should I buy a water heater for the winter months?
Second, I think one of my fish may be developing fin rot. He's active and hasn't lost his appetite, but I've noticed a few black spots on the tips of his fins, although the others are white tipped. Also, he seems to be changing colors back to the green color he was when I originally bought him from the red he is now. Is this a bad sign, or do bettas change fin color over time? (Or am I altogether overly paranoid?)
Thirdly, do they have any response to a Circadian rhythm or are their brains to small to distinguish what times of day and night day and night should be?