I am having a problem keeping my baitfish alive overnight. I catch perch and keep them in an ice chest overnight. I have an aerator with a submersible pump. The next morning the water is hot and the fish are often dead. I think the pump is warming the water.
Rocky I save 20oz. and 1 liter soft drink bottles and freeze water in them
and add them to my bait chest as needed to keep the water cool. Just put
them in and let them bobb around it really saves your bait.
I went out side to one of my tanks and took a pic of my thermometer trick. Its a regular meat thermometer, a thin piece of pool noodle with a cut slip bobber in the middle of it.
This is a bream tank and I try to keep it close to 70F. At 78F and up they have a harder time to get oxygen so the lower the temp the better they will breath.
As a general rule I put in 1 fish per gallon...depends on the size of the tank. This tank only has about 25 bream in it atm, with 25 gallons of water. Never use ice from the store, it has chlorine in it, use like these guys said...frozen bottles. Cool it about 2 or 3 degrees every few minute or else they will die from cooling to fast.
I also keep white perch, small stripers, crappie, and bass a lot of times....