You can get rid of them via hydrogen peroxide (h2o2) but you MUST wear protective gear, gloves, goggles, chemical mask, take the culprit rocks out of your tank, hold the affected side down in a dish of drugstore H202 for 30 seconds, then rinse liberally under your sink faucet. Then set them into a bucket of discard salt water for 30 minutes before returning to your tank: the bubbles that come off are pure oxygen, which can burn and kill other life. The reason for protective gear is in case there should be poisonous palys or other problems on the rock. Everything on the rock will be killed. But the bacteria inside the rock will be fine, and it will resume function as live rock.