The livewell just had a recirculate feature. For about a buck he turned it into a nice system, which will surely keep those fish alive! Most modern livewells already incorporate something similar however this is great for anyone with a jon boat or a livewell that doesn’t already include this. Another way in doing this is by drilling a hole in the water output PVC pipe and inserting a tube to fresh air, or if the PVC pipeing is already above water just drill a hole so air can be sucked in.