I am setting up tank #2...was offered ANOTHER tank for free
I'm thinking of using my biofilter and connecting all three tanks...In my assembling..I found people use all kinds of stuff in their filter for surface area. I have a HUGE container of hydroton...can I use this as surface area media in my biofilter?...as well as in grow pots that will also be circulating water back to the tank? I've had loose clay in my bubble buckets when I use hydroton..no problem for plants...fish?

As for food...I'm looking for suggestions for an organic food for tilapia. Are there any that are actually organic?