both of my tanks came with bio ball in the one tank iset it up with bio ball in the other i stared with lr rubbal. now i finaly got some more rubbal and started to replace all of the other tank bio ball with the rock. but i didnt have enuff so i put some bio balls back in till i can make a trip to my lfs and get some more rock. so now i have my 30 gal running good and my new 12 reef ready to go for more corals and things
