Hey, glad to hear things cleared up.
Bio-balls are a type of filter media for bacteria-homing. The balls have grooves and fins for a larger surface area. This is so that beneficial bacteria can propagate and colonise in the media. How to use? Buy a big bag from LFS, get a netting bag, fill it up, tie it loosely and dump into one of the compartments in your filter. I'm assuming you have an outdoor filter with various compartments. And that's it. I have bio-balls in my sump tank from day one and have not touched it ever since (from Oct last year).
