I have taken a fancy to SPS and am hoping a lighting upgrade will help with coral color.

After researching coral coloration and lighting intensity in reef aquariums I came to the conclusion that I wanted to upgrade my lighting system. My current setup is all T5's and does a great job with my soft corals and LPS corals. The problem is since I originally set up my reef tank (almost 1.5 years ago now) I have gotten interested in SPS!

My current lighting system consists of four 2x39w T5 retrofits with IceCap reflectors and Advance T5 ballasts.  I am using all Geissemann lamps with one of each spectrium they offer:

Back
Pure Actinic (420nm)
Aqua Blue (11K)
Midday (6K)
Actinic+ (460nm)
Front

Still space left to expand! Here is the PAR my lighting system generates as measured on my tank when I first set it up:



Now this is a fair amount of PAR but it is more in the realm of medium to medium high light. Based on my recent "How much PAR" research I would like to see a range of about 200-600 PAR (more appropriate for SPS) from the bottom to the top of the reef. Maybe 800 to 1000 PAR at the top of the tank. This means I need to almost double my lighting intensity.

What's next?
I have thought about what would be the best way of increasing my lighting intensity and at the same time increase coral coloration. I went back and looked at some very successful reef aquariums from Reefkeeping Online Tank of the Months and noticed that an overwhelming majority used metal halide lighting in combination with some fluorescent (VHO, T5 or PC) supplement. I decided to add metal halide pendants to my canopy to increase my lighting and round out my spectrums. Here is the new plan:

3- 150w HQI Pendants
1- Dual Galaxy Electronic 150 HQI Ballast
1- Galaxy Electronic 150 HQI Ballast
3- 150w AB 13K lamps     
+
4- 36” 2x39w IceCap T5 Retrofits
4- Actinic +
4- Pure Actinic

So basically I am going to keep all my T5's, spread them to the back and front and add the three 150w HQI pendants. The only issue I have with this plan was that I only have about 6.5" width in the middle of the canopy to work with.

Which Pendant?

This is the smallest 150w HQI pendant I cound find

The good things about this pendant is that it is only 6" wide making it an easy fit with the space I have left. The other good thing is that it is only 3" tall so it will not extend that far down hopefully making cooling easier and limiting splash from the tank. The basic shape/design of the reflector seems like it will provide some decent light output.

Which Bulbs?
I once had a 15g nano reef that I kept SPS in. It used a MH/PC combo with a 70w Aqualine Bushcke 13K HQI lamp and Dual Actinic lamps. This lighting combo has been and still is my favorite looking lighting setup that I have used on a reef tank. I am going to try and re-create that look I had but on a slightly larger scale. The AB 13K lamp is actually a great 10K lamp. It burns at a 10,000 kelvin rating and has a nice crisp white appearance with almost no yellow tinge.

This should balance well with the T5 actinics. I may try some of the UVL Super Actinics along with the Geissemann lamps. The 450 watts of daylight spectrum from the HQI pendants should work well with the 312 watts of T5 actinic.