I've had
Bluegill for a while now. I find them to be hardy, adaptable fish.
Buy a kit and check you water quality. Very important. If the nitrites rise above .25 ppm do a 25% water change. I've been doing that to a 20 gallon unit and I'm almost there.
I have a 48 inch long, 18 inch high, 11 inch wide tank. (41 gallons) Barely big enough for the 5 in there. Ranging in size from 2 1/2 inches long to 5 inches long.
I'm looking for a bigger tank.
And get max filtration too. Filter should be minimum 2 times the capacity of the tank. 3 times is better. Bluegill are dirty fish. They need good filtration.
The ones I catch adapt to the tank in a day or two.
Blood worms are great food, either live or frozen. They love them. They also like crickets, live of course.
The ones I have chase each other around. Except for one extreme bully, he is in a tank by himself. I'll check later and see if he will play nice with the others.
Lastly, the Bluegill I have are like my boys. I walk in the room and they line up waiting for me to feed them. Honestly. I reach in a move things around (after they have moved things around some) and not only do they not swim away, they swim up to check me out. Sometimes I have to push THEM out of the way, and then they come right back! So cool. They are so interesting in their habits. If you can get the water stable in high quality, you will be rewarded with some extremely interesting critters, in my opinion. And watch out. They are aggressive and will eat most other fish and shellfish.