My "livewell" began as a bait tank, which I use to hold bream and shad, because I always put fish I plan to eat on ice. When I fished in a local tourney I used it to hold those fish, and it worked very well, since the requirements are the same. It has can recirculate and aerate water, and also pump fresh water in from the lake and dump the old, but requires two pumps. The plumbing system looks like it was designed by a drunk, but it works... At some point shortly, I plan to add a filter... Then, it will be perfect!
If you are fishing in really hot conditions, you need something additional to cool the water, as said above...
My tank is a fifteen gallon white bucket that I got from a restaurant supply store, with a lid. However, I rarely need to cover it carrying ten gallons of water... The bucket works for me better because of the smaller footprint in my boat, where floor space is limited....
I got the idea from watching YouTube videos. There are a lot of ways to get there, but all of the requirements are the same.
I do think having higher sides is an asset...
In this pic, the dump and pick up hoses are not attached, because I was fishing for just a few hours at night.
Good Luck...
Look for the old Carolina Skiff
Loaded down with too much gear...
LINES IN!