Need Your Thoughts

[jarred1]

So I am getting a new 150w Metal Halide light fixture and want to supplement it with an LED strip. There is two ways that I can put the LEDs on to the light fixture and want to know which way will I get the best coverage. The tank is 24 inches long and the light is about 12 inches long and will be centered over the tank. I will be using 6 Cree XR-E Royal Blues. The light will be about 8 inches off the surface of the water. Let me know which one will give me a better spread and do you think I should use optics?

So here are the ways that I can have it done:

 

[wld1783]

jarred1

Thermal Management is key to LED longevity. MH are hot and so are their housings. I would not recommend what you are considering. Normally LEDs are a replacement for MH

Bill

 

[jarred1]

I have an all LED fixture now and they are making my zoas brown out and shrink in size. I will have the LEDs about .5" off of the Halide and these fixtures don't run as hot as others for some reason.

 

[CoralFever]

What LED fixture are you running now that is browning them out? I would agree with Bill, probably not the best idea to mount them directly to the MH housing. How about making a small aluminum frame around the MH housing? You could make it out of the aluminum U channel or L stock. 3 on each side will give you better spread.

 

[jarred1]

Oh, you all thought I was going to mount them right onto the Halide, I was planing on using a heat sink as well. The halide does get really really hot so if I do plan on using LEDs I have to figure out a way to mount the LEDs a little bit away from halide light. Any suggestion on how to do that?

The LEDs were a DIY build with 16x3w Cree XR-E on a 20g tank. They are just way too much light for the tank.

 

[RonMidtownStomp]

I think your conclusion about the 16x3W Crees being too much light for the tank is incorrect and that you have something else going on. Bill is right and you could certainly light that tank with LED's.

The concern about heat is only valid if you plan to run the LED's at the same time as the Metal Halides. As long as you only have one or the other running at once, the MH heat should dissipate very quickly with the Aquamedic pendant and the aluminum housing.

 

[fragman2]

I have a MaxSpect G2 110Watt fixture over a 20 gallon breeder (frag tank) The bottom is completely covered with Zoas and Palys and they are doing quite well no browning out and I have A LOT of light. There are over 30ea 2.8W and 3.0 W LEDs. My Zoas are coloring up big time! My guess is that you need more LEDs.