DIY terrarium lights

Jean Kaye

Newly Enlightened
Dec 9, 2012
Hi all!

I've started a new vivarium project but the shape of the terrarium is making things complicated and I must build my own light. The dimensions are:

Width: 16 3/4" 43cm
Depth: 14 3/8" 37cm
Height: 64 1/8" 163cm

So it's quite narrow and tall. In the project I need to avoid heat build up and still get the brightest possible lighting. So I'm thinking about using 7-10 Cree XM-L leds (white and 2-3 warmwhites) with narrow 16o​ optics.

So currently I'm stuck on cooling:
Can one run white XM-L leds with maximum recommemded 3000mA with passive cooling? I'm thinking about heatsink like this: but I'm worried that leds might overheat...

Does it make any difference if I switch star to Copper PCB?


Mar 16, 2011
What you need is a large heat sink made for passive cooling like Forget about those little pieces of aluminum unless you want to cook you leds. You need to get rid of approx. 75W of power through natural convection. The one in the link is 400mm wide and you can get it in 400mm length, but it weighs 14.3kg. And leds will be grateful if you use those LT copper PCBs. Those are really good since they use direct thermal path.