I would like some opinions on crushed coral for base media for reef system. I currently have 90 gallon reef, half dozen corals and half dozen fish. Running trickle filter, seaclone protein skimmer, uv sterilizer, have live rock and sand base media. I have problem with green hair algae, trouble with keeping PH at 8.3, trouble with keeping calcium above 300. Using kalk with top off water and adding PH buffer. Using calcium supplement two to three times a week. Tank been set up almost one year, and I have 30 years of freshwater experience with breeding of cichlids. I know with freshwater, when algae became a problem, I would do part. water changes with gravel vac. I am currently doing part water changes every two weeks, I can not do sand vac. cause all of the sand would come out with water. I was thinking with crushed coral as a base, I could do vac on crushed coral and would help with PH and calcium problems. My water comes from private water well, filtered down to 1/2 micron drinking water filter. WOULD USING CRUSHED CORAL HELP THE PH AND CALCIUM AND I WOULD BE ABLE TO DO GRAVEL VAC WHEN DOING WATER CHANGES. Thanks in advance.