Muriatic acid but you will KILL everything on there, and I mean everything!
Fill trash can with water and mix in there about 10 to 15% of the gallon MA, have a pump running for 24hrs.
Dry your rock three days in the sun and have it cured in the same trash can this time with fresh water and after a few days have salt added to it in order to run a skimmer to get most of the phosphate out.
Replace all plumbing from your tank and clean all equipment with MA too.
It will take some time but mean while you can have your corals in a frag tank with a small fox face as he will clean your corals
Fill trash can with water and mix in there about 10 to 15% of the gallon MA, have a pump running for 24hrs.
Dry your rock three days in the sun and have it cured in the same trash can this time with fresh water and after a few days have salt added to it in order to run a skimmer to get most of the phosphate out.
Replace all plumbing from your tank and clean all equipment with MA too.
It will take some time but mean while you can have your corals in a frag tank with a small fox face as he will clean your corals