White growth on live rock?? Newbie sorry

I am new to the hobby so sorry if this is a common thing to have happen. I have googled the heck out of this and got nothing. 29 gal tank 4 months old 2 clowns 2 damsels 2 small crabs 1 shrimp 5 snails 3 sets of coral trying to start on different live rocks. Uv light and hang on back protein skimmer LED full spec light.

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