um-
d ske
That I understand. I think, so long as it doesn't pop off, I'd could integrate a check valve. Just would suck if it popped off underwater and then water seeped in an made a bigger mess. What I am building is similar to one of these:
I prefer lithium-ion as they last longer and an HID for the quality and quantity of light. Simply need a battery setup that will fit into a canister like the one on their page....
BTW, thanks for your input James!!!