| Re: Where do I put crushed coral?
Crushed coral will raise your pH, but I am already assuming you are aware of this and this is actually what you are trying to do. In one of my old cichlid tanks I had entirely crushed coral substrate. I have no experience with putting it in a bag in the filter (although this should work just fine) My pH from the tap was about 7.6, which is relatively high, but it bumped my water up to about an 8.2-8.3 which was a lot better the cichlids I used to keep. I also loved the look of the crushed coral, and I loved watching the cichlids play in it also. | 
