evaporation is just something all reefers have to deal with. when adding water back into the tank, make sure to add only fresh water, because the salt content stays in the water. that's how the salinity levels fluctuate so much on saltwater aquariums. something you could do, is get your glass top, but hook up an airstone to your tank and make sure you have a lot of surface aggitation (point the powerheads up). the only problem with that is if you end up with a sponge and it dies from being exposed to air, your tank will be nuked. (unless it's a really really really small sponge).
hermit crabs won't empty the snail shells THAT quickly...unless you starve them or don't give them bigger shells to switch to.
most protein skimmers do need a powerhead. if you end up getting a skimmer with a powerhead, make sure it has a venturi system on it. that's the best way to go imo. i have a prizm skimmer, and i used to turn it off every night before i went to bed, but i'd have to spend like half an hour in the morning trying to adjust it again. i don't use that skimmer anymore.
i don't understand that jlaquatics fixture...a 55w bulb alone is 23" or 21" i can't remember.... so how could a 96w bulb be 20"? email them and ask about that before getting it. if you do go with Island Aquatics, get a retrofit system. they sell the good stuff there...that might also be why it's that expensive.
Tim
