Light hight for my tank

Simple yet never a simple question when it comes to lighting, but here goes.

I have a 40g breeder with a t5 teck lighting 4 bulb unit. Lighting is 2 blue + , a super actinic and a 12k white actinic. Bulbs are ATI and UVL. So really good bulbs. My tank is a mixed reef with sps and lps. What I'm trying to figure out is how far above the water my lighting unit should set and also a round about number of how from the surface should my upper most live rock be that my SPS are on?

Like I said simple yet never simple.

Some of the SPS that I'm talking about are:
Green Bali slimer
Indo purple tip straghorn
Birdsnest

As for other stuff that I have but keep on the bottom/sandbed
Clam, torch, Elegance.

Thanks for any and all advice.

 

You could do it on the legs or up to 8" easy.

 

Height depends mostly on light spread. the farther up you move the light the more it's going to spread and the more light you will cast out of the tank. I would start off on the legs and work from there. For SPS under only four bulbs I would try to get the rock within six inches of the surface, but keep in mind this will limit room for them to grow up.

 

At rhe moment I have the light about 6 inches above the water and the highest area of the rock is about 6 to 8 inches under water. I also make sure that the lighting is directly over the corals.

As far as only having a 4 bulb unit, the light covers the tank good. Their is just a small area about 5 to 6 inches in the front of the tank that the light isn't over top of but that area is just the sand.

 

You should be fine with that. IME you can have your SPS down to the middle of the tank easy and they will do well.

 

k ill just keep them where i have them at for know. it just that my birdsnest coral is about 2 to 3 inches off the SB and its color still looks a little faded.
the underside of the birds nest looks to me like it has better color.


Cant really see the underside of the coral in this photo, but the green polyps is a much darker green. any thoughts?

THIS IS WHEN I FIRST GOT IT. back in Feb 2010. so its growing great i guess
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