how high to mount leds?

I have a set of leds on the way. My only concern is how do I figure out how high I should mount these. I'm building my own brackets that will come up from the sides of my tank then over the top to hang these fixtures. I would like to have them built before the lights come in just not sure on how high they need to be. I have a 55g tank here are the specs on the lights

50 watt using 14 3W bright white,11 3W 460nm blue, 18000K white 60 degree view angle, Pure 450-475nm spectrums fixtures are 19in in length and ill have 2

 

Well that all depends on does the unit have optics, is it dimmable. these two things will determine how high it should be placed.
I have mine with no optics about 8 inches above the tank, it is 18 inches high and i have good par to grow sps, and clams on my sandbed.

 

No dimmers.. StarkLED 50W LED Aquarium Light | StarkLED Online Store | State-of-the-art Aquarium LED Lights!

 

Bump....

 

This light seems to good to be true type situation. a fixture packing 24 cree leds with drivers and everything for 240 is almost too cheap. Secondly for a new company like this with no product reviews is also something to watch for. it uses blue leds and no royal blue which roi think is bad. It says cree leds but for the price its being sold at they are probably low end bin cree diodes. after looking at the website they appear to be looking like knock off OCREEF cree 60w lights. But at the big price difference, thats whats pointing to lower end diodes being used.


White(18000K): 12x3W
Blue(450~475 nm): 11x3W
UV(380 nm): 2x3W
LED Type CREE XP-E Blue & XP-G White

The cree xpg white series it advertises does not make a 18000k led. Secondly i would not use a uv diode at 380 nm, this would lead to harmful rays being created which can bleach and hurt coral. It says pure blue, and then also says it only uses xpe blue 460nm leds. Theres too many things wrong in their description and from look of website. I would see if you can get a refund personally. I just built 3 different fixtures using different leds and learned quite a bit from this. This is my opinion. Hopefully it may help you.

 

Not needing reviews. I ordered white in place of UV and cree is only in 60w fixture not 50w it lists the brand of other led. I have a Guy who grows corals and uses these lights with no problems

 

Plus I got them even cheaper at 165 a fixture lol local Guy has dealer account

 

You are the second person that said something though.. I've already paid for 1 up front thinking about canceling the other 1 and going with metal halides... maybe use the one Ibuy to put over a nano

 

yike those do look pretty "made in China" to me

 

the 50w unit you linked in the details part says it uses cree thats why i said it. But your saying the 50w doesn't come with cree. That seems odd. secondly if you switched out white for the uv it came with that will give you 14 white leds and 11 blue, without dimmers that is a very white color combo. 165 is a decent price... but not if its gonna brown out your corals. I dont like to hate on companies i don't know but this looks like a good case of one. If you scroll to the bottom of the site you linked the only contact info relates to Agora Pacific Inc. They are a importing exporting business based out of LA. This company StarkLED in which you said you purchased this awesome new light from only has 3 products available, all of which are re branded mass produced factory made fixtures not actually tested and built to grow corals, but a bunch of colors thrown together. Notice the amount of blue to white ratio and the use of only blue and not royal blue. A company making lights for your reef tank will know these little things. The company shows no relation to having any knowledge of being in the field of making these lights or having any knowledge of reef capable lighting so i can only assume they are pushing them because of how cheap they got them.

Also please look at
http://www.agorapacific.com/
under the links to click on it looks like they own StarkLED lighting, I would advice you to get a refund and stay away.