If I implied that they just be left in the bag, no they cannot. I would store them in a styrofoam container. The ones we used were in huge bags, the bags were in styrofoam containers with styrofoam tops and the styrofoam container was in a cardboard box.
I even had a battery powered air pump I used.
*180 gal Display, 100 gal basement sump, 33 gal refugium, 3x250 MH, 2x160 VHO actinics, zoos, some softies, LPS & lots of acros and other SPS.
*100 gal prop tank plumbed into main system w/ 2x96 PC lights and 1x150 MH,