You need to rinse it with tap until it’s clear
Two points about that:
It doesn’t kill bacteria off the rocks, tap water isn’t a sterilizer or lab techs wouldn’t need to use more to sterilize at the end of the work day. Tap water delivers bacteria, it doesn’t kill them in the way we’d expect
The ability to work with your new tank in a cloudless condition is priceless, the bacteria that are in live sand / caribsea is not needed. It’s in excess of the bacteria that cycling provides on the surfaces that count.
At no time is the bacteria in a sandbed the critical breakpoint in having ‘enough’ bacteria to run a bioload of fish and corals
The rocks are always enough, we remove sandbeds from full running reefs all the time in the sand rinse thread.