LPS Lighting

[CapitalO]

I have a 29g LPS tank (containing mostly trachs, euphyllia, acans etc) and I currently have a 2x65w coralife fixture (10,000k and actinic O3). I noticed that my corals lose some of their color, becoming slighlty more washed out over a period of a few months in my tank (all my corals have come from a tank lit by halides). I dont really want to invest in an expensive mh hood that produces more light than my corals prefer.. so after a few weeks of research, Ive decided to build my own hood using a 70w mh (13k aqualine bulb) retrofit and the guts of my existing fixture for supplemental lighting (actinics). My other conisiderations were using all T5's (Olliereefers tank is awesome), or using a 150w mh instead of the 70w.. there isnt a great deal of difference in cost, but in my experience my LPS tend to expand more and seem happier under less intense light.

 

[musty baby]

Depends on the LPS. What you have I think would be fine under more light, but any MH lighting I think would be a good start. I would personally go with the higher-power bulb, you can always raise it up off the tank or, what I would do, run it for a shorter time period if it makes any of your corals unhappy.

 

[nmprisons]

your lighting is absolutely fine for those corals ... how often do you replace the bulbs? What kind of reflectors do you have on the bulbs?

 

[CapitalO]

I thought about the reduced photoperiod aspect with a stronger bulb, It just makes more sense to me to use the lesser power bulb for a regular photoperiod. In nature deep water corals dont get blasted by a few hours of daylight at a time, its just less intense than shallower species with the same length of exposure.. well thats how i rationalize it, whether that makes a real difference in practice is another story .
nmprisons: yea I know my lighting is fine for my corals.. I just want to upgrade to higher quality lighting, not higher intensity. this is for reasons of coral color retension, aestetics and algae control. Also i know that the blue spectrum penetrates deeper into the water, so to simulate the spectrum at a deeper depth by using a bulb with a higher color temp. such as 20000K would this benefit the corals?