My current livewell only has a pump fresh water in feature not a circulate feature found on most boats now days.  My question is how often do you supposed I should be pumping fresh water in to cool the water as well as areate? I wont be able to run it 8hrs straight during the tourney or my battery would likely die.  What are you guys suggestions for keeping the fish healthy under these circumstances?

Frozen bottles of water and a small 12v air bubbler. Once you get your first fish, fill livewell and add a frozen bottle. This will keep the temp 5-10° below lake water temps and slow the metabolism and activity of the fish. You shouldn't have to keep adding water.

2 gatoraid bottles should keep you cool for an 8-10hr tournament, once it gets in 90° air temps I'll carry 4 frozen bottles just in case.

You could get a livewell timer from BPS for under $50.  You run your power wire between the timer and whatever you wan't to cycle.  You can set it to off, continuous, 1,3 or 7 minute cycles.  Each on cycle last for 1 minute.  I helped a friend do one and it works very well.  You can use it on a 12V aerator, or to cycle your main pump.  I would probably put it on an aerator. just so it was functional out of the water The frozen bottles really help as well.  He and I crappie fish sometimes and I've seen him keep minnows in his livewell for several days.

You should check the livewell water temps and during the summer keep the water in the mid 70's, frozen 1 pint plastic bottles of water work good.

Aeration is needed when bass are in the livewell, 8 oz ( 1cup) of over the counter 3% hydrogen peroxide to 15 gallons of water (average livewell size) will keep the DO level good for a few hours in an emergency. Adding surface lake water will add DO but raise the water temps. Using a 12V battery operated Livebait areation system also keeps The DO level up without adding surface lake water. Areation every 20 to 30 minutes for 5 minutes keeps the DO level up without running the system all the time.

Sure-Life Catch & Release should be added when you fill the livewell, check their site for livewell management vedio's.

Tom

Bottles of frozen water and salt are all I've ever used and I can't remember losing a fish due to the livewell performance.

I'd get a better battery honestly.  Once a fish goes in my livewell, the pumps stay on the rest of the day.  I don't have recirc in my boat either.  I switch them to auto which pumps in fresh water for 1 minute every 10 mins.  It works incredibly well.