I have a 180 gallon sps tank. Im running 3 XM 15k 250W metal halides, along with 8 T5's. I was wondering how far from the top of the tank should I keep them? I have nice reflectors from hellolights. At the time the bulbs are 14 inches from the top. I just moved them up a little today and it seems like the corals color looks better? Im wondering if some fading in coral was from the bulbs being to close? Any ideas? : )
SPS lighting
- Thread starter Treed
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Alex T.
Active member
Well, I don't know if the fading is definitely related to the halides. I have what some would consider an insane amount of light. Mounted in my canopy 11 inches off the water are four 400 watt Radiums in Lumenmax Elite reflectors. My tank is a 72L x 18W x 27H 150. I don't think my SPS have ever looked more colorful. Granted, my rockwork is only a little past half way up, but I like to keep clams on the sandbed and have SPS growing out of rocks on the bottom of the tank. 250 watt bulbs should be fine however the reflector will be the deciding factor. Even with 400 watt bulbs my Crocea and Maxima Clams wanted more light on the sandbed when I was running Spider Reflectors. A high quality reflector that can punch light deep can be hung higher than most and still give excellent par and spread without causing heat. Cheap spider reflectors need to be almost 4 - 6 inches off the water to have any affect, thereby losing the ability to spread the light out from a higher distance while not sacrificing intensity.
Which reflector do you have from HelloLights? I believe the main reflectors you see in most tanks these days are Lumenarc, Lumenmax, and Lumenbright. The Lumenarc can be more versatile as it can be installed in most conopies as is with great light spread, where as my Lumenmax Elites and the Lumenbrights create a high par spotlight that can burn corals if they're hung too low. People run Lumenbrights at 16" or more off of the water surface with excellent results in growth, par measurements and light spread.
Which reflector do you have from HelloLights? I believe the main reflectors you see in most tanks these days are Lumenarc, Lumenmax, and Lumenbright. The Lumenarc can be more versatile as it can be installed in most conopies as is with great light spread, where as my Lumenmax Elites and the Lumenbrights create a high par spotlight that can burn corals if they're hung too low. People run Lumenbrights at 16" or more off of the water surface with excellent results in growth, par measurements and light spread.
http://www.hellolights.com/250whlmetalhalideretrokfitkit.aspx Those ones are what I have
Alex T.
Active member
Well, I don't like to rain on anyone's parade, but those reflectors are the generic Spider reflectors I was speaking of in my previous response. Absolutely abysmal performance regarding penetration and light spread. Also, you have one of the least desirable bulbs for SPS. The XM 20k actually puts out more par than the 15k per Sanjay Joshi's lighting guide that compares ballast and bulb combinations. I know that seems counterintuitive but the results are right there to read for yourself. http://www.manhattanreefs.com/lighting
Being that you're running 250 watt bulbs compared to 400's, your light spread and penetration is even that much weaker than mine was when I was running the spider reflectors. On a tank like yours you would see an incredible and noticeable difference in overall spread and brightness if you switched to a Lumenarc or Lumenmax Elite. They're expensive but worth every penny. There are threads on RC if you do a search that show the par difference and growth rates when a better reflector is used over the Spiders. I think you'll agree that in this age of escalating utility costs, we may as well get the most out of the electrical usage we pump into our lighting systems. A better reflector will most likely allow you to raise them higher in your canopy and generate much less heat in the water as well. You'll also most likely save money in the long run because you won't have to run them as long due to better penetration, intensity and spread over your SPS corals.
Also, you'll be able to eliminate some of your t5's because they simply won't be necessary. I don't know which ballasts you're running either, but a 250 watt Radium 20k would offer much more par and a more crisp look than your 15k XM's.
Again, I'm just trying to be upfront and honest with you. I ran the spiders for over a year and wondered why my corals wouldn't grow as well as in other people's tanks. Even with 400 watt bulbs, I was very disappointed. When I changed out to Lumenmax Elites I had to acclimate my SPS to this stronger lighting and the growth and coloration is absolutely unreal. There are plenty of old TOTM recipients that have used spiders in the past, but when you look at the lighting duration compared to what people with better reflectors are running now, it's not even close. Much less time with the lights on with better growth and coloration while not transferring more heat into the system and saving on electric? I'll take that any day.
Being that you're running 250 watt bulbs compared to 400's, your light spread and penetration is even that much weaker than mine was when I was running the spider reflectors. On a tank like yours you would see an incredible and noticeable difference in overall spread and brightness if you switched to a Lumenarc or Lumenmax Elite. They're expensive but worth every penny. There are threads on RC if you do a search that show the par difference and growth rates when a better reflector is used over the Spiders. I think you'll agree that in this age of escalating utility costs, we may as well get the most out of the electrical usage we pump into our lighting systems. A better reflector will most likely allow you to raise them higher in your canopy and generate much less heat in the water as well. You'll also most likely save money in the long run because you won't have to run them as long due to better penetration, intensity and spread over your SPS corals.
Also, you'll be able to eliminate some of your t5's because they simply won't be necessary. I don't know which ballasts you're running either, but a 250 watt Radium 20k would offer much more par and a more crisp look than your 15k XM's.
Again, I'm just trying to be upfront and honest with you. I ran the spiders for over a year and wondered why my corals wouldn't grow as well as in other people's tanks. Even with 400 watt bulbs, I was very disappointed. When I changed out to Lumenmax Elites I had to acclimate my SPS to this stronger lighting and the growth and coloration is absolutely unreal. There are plenty of old TOTM recipients that have used spiders in the past, but when you look at the lighting duration compared to what people with better reflectors are running now, it's not even close. Much less time with the lights on with better growth and coloration while not transferring more heat into the system and saving on electric? I'll take that any day.
