are you sure they are pests an not something that can live in your tank 'symbiotically' with your stock? drying it out would create massive amounts of die-off, and therefore would start a big cycle when you put it back in the tank. on top of that, you would lose all your beneficial bacteria. you couldnt dry out a portion at a time, because whatever 'pests' your trying to get rid of could just move onto the last batch of rock and just stay in the tank while you start another batch. also, depending on the size of your rocks, it could take a while to completely dry out live rock, and a lot of hitch hikers can survive periods of being dry by going into a state of suspended animation. depending on what you're trying to get rid of, there are traps and different processes' that can rid your tank of these critters. any information or pics would help us to give these things an ID (if you dont know what's in there). either way, i dont think drying out the rock will be effective and certainly not convenient for you. just my $0.02
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