Submerging a CoB LED

[8bit_brain]

I want to build a lamp for my 500L aquarium. I want 3x 20W LEDs (I hope 60W it is enough). I already purchased an aluminum bar of about 140 x 4 x 0.5 cm and some people on electronics.stackexchange.com (I hate that site, I find people on this forum more polite AND MUCH MORE HELPFUL) that it might not be enough to dissipate the heat from those 3 LEDs.

Since I want to mount this INSIDE of the aquarium, I wonder if it might be possible to install the LEDs on aluminum and submerge them (or have them float). This will DEFINITIVELY eliminate the overheating problem.

Any idea on how the LED could be electrically insulated, protected from the water and made the float?

I am open to any ideas. I am thinking of epoxy. LOTS OF IT!

 

[duke37]

I think you will have problems. 60W will probably cook your fish unless the aquarium is very big.
You could use a copper bar or pipe with the LEDs soldered to it for heat sinking and then pass cold water through the pipe to take away the heat.

The assembly could be placed inside a plastic bottle

 

[(*steve*)]

60W of LED lighting is probably the equivalent of the or four 100W bulbs.

The first question is whether you need that much light.

 

[8bit_brain]

the aquarium is big (500liters).

 

[Harald Kapp]

the aquarium is big (500liters).

You're probably better of then using many more smaller LEDs which will help to

1. evenly distribute the light across the tank
2. evenly distribute the excess heat across the heat sink.

 

[8bit_brain]

>evenly distribute the excess heat across the heat sink.

It seems that my aluminum bar can only dissipate 2W.
I used this calculator:
http://www.qdusa.com/techsupport/thermalCalculator.html

This is why I have to submerge the bar in water.