DIY led

[Frikkie]

Hi everyone, my name is Frikkie, I'm from South Africa. I have been reefing for the past two years, i started with my dads 20 year old 5.5ft reef tank that had been standing empty for 18 years. I cleaned it up and disassembled it then rebuilt it. And now I'm upgrading to a 7ft tank.

I'm busy with a diy led for my 7ft mixed reef, currently i just have softies and lps, and with the new lights hopefully sps.

The tank itself is 7ft long, 2ft wide and 20 inches tall. Also it is eurobraced.

I have built many diy leds for myself and friends, so i have lots of experience doing this, but with 3w leds.

So my question is with regards to the leds. I have 5w cree xt-e royal blues and cool whites, will i be able to get away with less led's than the regular 3w led's if i work on the same final wattage? My aim is two 200w units, running them at full capacity.

I am powering them with meanwell 1500ma drivers with pwm.

Let me know what you guys think.

Thanks
Frikkie

 

[dragon99]

Light dispersion is going to be the key. If you have a lens that spreads the 5w LED out well, you should be fine. With ~ half as many LED's getting even PAR across the tank will be more challenging, but not impossible.

 

[Frikkie]

I see. Well i have 90 degree optics and can hang the lights a bit higher or should i go without optics and put them 6" above the water line? I drew the ray diagram in sketchup and it looks like no optics at 6 inches will give me good coverage but im worried about intensity

 

[Irsug1]

At 20 inches of depth you should be fine without optics for intensity.