waterproofing LEDs?

What's the best way to waterproof multiple LEDs connected in series?
I just figured out that If I could find some way to do this, I'd have a very reliable, simple and easy-to-implement way to find the water level of my bong watercooler. Also, I want to light up the water vapor that come out of the top of the bong. Will normal insulated wire be fine inside a bong (ie in steam and underwater) or is there a special type I should get?
Thanks.

I would think imbedding all of the LEDs in a bunch of plumbers goop would be the easiest solution. Find a long, thin mold that it won't stick to, fill it with goop, plop the LEDs in in series and let dry.

btw, wouldn't you want the LEDs in parallel? I would think putting them in series would cause each LED to be dimmer than the one before it.

I just did this...sort of.
The bottom of my bong that I took out of retirement had lost it's square knob in the screw cap. (my direct die cooling flop)
I covered the hole with a piece of plexiglass JBWelded over the hole.
Just for giggles, I took 5 series led's that have a flat top on them instead of the usual rounded style, and superglued them to the dry side of the plexi. This lights up the water really nice.

To waterproof a string of normal ones, you could lay down a bead of goop or silicone on a piece of wax paper or sticker backing paper. Then set the presoldered diode string into the bead with the wires down and the tops sitting out of the silicone. This would waterproof the wiring, and not interfere with the light. The insulation on the power wires should be pre attached to, with the ends of the insulation also in the silicone. Wire insulation is waterproof. When it's dry, you can apply fresh silicone to the flat side, and glue it right to the inside of the bong, taping in place until dry.

ps. 5 diodes in series do light up nice and bright (and equally so), and don't require any resistors when run on the 12volt psu bus.

Thanks, Diggrr. Somehow I knew that you'd find this thread. What you suggested was what I thought of too, but I wasn't sure if it'd work, and you covered the specifics.
Looks like that's what I'll e doing then. Thanks!

Krusty said:

btw, wouldn't you want the LEDs in parallel? I would think putting them in series would cause each LED to be dimmer than the one before it.

Click to expand...

Its better to wire LEDs in series groups, not in parrallel. The mA can be controlled much easier when the LEDs are in series then if thier in parrallel. The mA will vary to greatly if you wire the LEDs in parrallel.

Besides, the average LEDs fall around 1.5-2.3 volts, so its easier to wire 5 LEDs in series and use a small resistor value.