Hello everyone, sorry if this bothers anyone as it was SLIGHTLY covered in one of the stick forums, but it didn't really answer my question. At the end of one of my last threads, I was suggested to fill the remaining space on my filter with bio balls, ceramics rings, etc. I looked into bio balls and their distribution of oxygen and good bacteria really caught my interest, now my goal is to find good priced ones. If anyone could let me in on any good deals with fair priced but still good quality substrate that gets the job done such as bio balls I'd appreciate it.