UF-2100 better waterproofing???

i have an UltraFire UF-2100 which is my 'big' flashlight/emergency light for fishing. it sits in front in a holster on my wading belt and is subject to submersion occasionally. regardless if it is submerged or not, however, i rinse all my gear -- including my entire belt -- in fresh water before storing. well, this last time out it did all that and a week later, my light wouldn't fire up. i disassembled it and found water inside the main tube as well as fogginess in the lens. the switch also seemed to have some signs of water. the battery was dead so i tested with a fresh battery and it seemed to fire up OK. as full disclosure, i am using a non-stock Solarforce clip on this light which gets pinned between the body and tail pieces.

the reason i have this flashlight for fishing is b/c of it's brightness, slim form-factor, and the fact that it has an SOS mode. i absolutely need it to not fail if i get injured, swamped, or swept off a jetty at night so the fact that i found water inside is concerning. am i asking too much of this light or is it just a matter of adding some beefed up o-rings? i would rather use a light with a beefy screw-on clip than ditch the clip on this light so if that's the cause, i'll look at other options. if i can add o-rings to the clip area, i'd prefer to do that.

my fishing usually entails some wading so the light will get submerged or, at the very least, splashed. submersion can be for hours at a time. if you guys/gals have suggestions for a better, bullet-proof light for my needs (still 'budget') i'm all for adding to my collection.

thanks!

I usually waterproof my heavy use lights. Teflon tape on all non conductive threads. Oversized o-rings. Tighten the ring down on the tail switch, also grease around the rubber boot where the boot presses against the inside of the tail cap. Use a plastic washer between the boot and the switch if one is missing. Don’t forget Teflon under the bezel and an o-ring on both side of the lens. Some of my SolarForces have been at the deep end of the pool for 2 days. Never tried waterproofing a side switch yet, looks like a pain to do.