I was poking through the Bait Tank Section and really didn't find the info I was looking for.. I was recently given an old pepsi cooler, the type you see in the store where the sodas are on ice, wish I had a camera, it has a drain at the bottom with a shut off... my thought is to create some sort of gravity to cycle the water without having to spend much money... the tank probably holds 20-25 gallons of water... the diameter of the drain looks like I could attach a garden hose with a hose clamp to it... do you guys have any ideas on how to cycle the water to aerate it and possibly filter it without breaking the bank, and driving 90 miles to the nearest Home Depot... I have a local hardware store and my grandfather is a plumber and has various parts I could snag, I'm just having a hard time visualizing it...Help..!?!