My Bettas belly

Question
I have had my betta fish for about 4 months now and about a month ago I brought him home where my parents have been taking care of him (I was at college and thought the transition would be easier if I brought him home in warmer weather). I have a 1 gallon glass tank for my fish. At school, he was very active and had quite the personality. At home, he isn't as active, yet seems to be fine. I am guessing that he just likes to be around people. Coming home after 3 weeks, I noticed that there was a bump on the bottom of my fish's belly- more toward the head and stops before his tail. I have been told that my dad really enjoys feeding my fish and probably gives him too much food. He acts fine, and is still eating. What do I do? And I have been reading here that you should only change 25% of your fish's water every week. I change all of the water every week and my fish has been fine. Why is it necessary to only change 25%?

Thank You
Jessica

Answer
Hi Jessica;

You are doing great with maintenance so keep doing what you are doing, especially if your tank doesn't have a filter. If your tank has a filter, you only have to change 25% weekly, but it's okay to change all of it if you want to. I don't recommend the same for other types of fish because they have different needs. Bettas are pretty unique.

Your dad needs to know that a fat betta is not a healthy betta. Most people don't know it but fish can suffer from some of the same obesity effects on the organs that people do. He could also become constipated from overeating and it can be fatal in bettas, or at least shorten his life. Constipation can cause intestinal rupture and swim bladder failure. It's best to avoid it in the first place. Feed him only enough food twice a day that is the size of his eyeball. That's how big his stomach is. More than that will risk his health. Your dad could feed tiny chunks of peeled cooked green peas 3 or 4 times a week to help his digestion but he still has to cut back on food. Peas act as a laxative. If they sink too fast for him to get, hold it on the end of a toothpick for him.

I hope he does okay...

At Your Service;
Chris Robbins