Valid points. My reason for Marco rock was to be done with unwanted hitchhikers. After all people go through alot of trouble qt'n fish and coral. Dipping and dosing. To turn around and dump rocks pulled off the breeding ground of these unwanted pest.
Answer to pest free live rock: man made ocean cultured live rock or old live rocks from fellow hobbyist. The only pests that got in my tank was through frags.
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You wouldn't want to see my tank. I don't use fancy equipment and I am a noob