Boiling water is still 100C (212F) regardless of whether it's a gentle boil or a rolling boil.... granted the pot is hotter with the rolling boil and some heat might transmit straight from the pot to the shells.aussieafricans said:
I didn't think to boil my shells, I'm not to the point of adding fish yet though. Yesterday I cleaned mine out... dumped them all in the 29gal tank and filled it with water, blowing the water into the shells. It filled up before I got all the shells cleaned out (yes, I have alot of shells), so I pulled out my as-yet-unopened sump pump and used that to finish cleaning out all the shells
-Rick (the armchair aquarist, who is cleaning several hundred shells instead of several shells)