Bleaching rock question

I think of the holes in rocks as shaped much the same as in a sponge. Holes and crevices on all side going down to dead end in the rock. Since water will not force air out of and overturned glass, there is no reason to think it will enter any holes on the bottom of a rock setting in boiling water. That leaves anything in that hole to potentially live through the boiling unless we boil the rock for hours long enough to actually heat the rock itself to a killing temperature. Then the remains of anything killed is still left there as an organic to pollute the tank. Bleach works chemically to react with organics. As it does it reacts and fizzes and penetrates these tiny cracks much better than simply soaking in water. It also reacts with any little bodies in the holes so that they are sterile as well. In a bleach soak with turning the rocks over and giving it plenty of time overnight to soak in, there is little space in the rock that is not sterile when done. A bleach soak just works better to sterilize things.

For the worries about the chlorine, it just takes a bit more thinking. By nature, liquids are easier to contain than gases. You can hold liquids in bottles like soda bottles that let gases escape. Ever buy an old bottle of soda and find it totally "flat" because the gas has escaped?
Combine this with the fact that chlorine is a gas by nature and you can see that if it penetrates an area as a liquid, it certainly will have no problem escaping when it becomes a gas.
Simple as soaking it long enough to penetrate, rinse it to dilute any chemical that might be left, and then let it air dry for the gas to blow away. I have no argument with adding a bit more dechlor but I don't find it needed as the chlorine will combine with air and drift away anyway. It should be noted that chloramine as used in lots of water treatment does not dissipate the way chlorine does so we use chemicals to remove it.