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Metal Halide Lighting

I have a new tank. 36" wide by 18"deep by 24"tall. I have a 250w metal halide bulb. Will this be sufficient light . My fixture also contains (2) 96w actinic bulbs as well. Also I am reading about UV filtering. What is that and how do I know if I need to filter my light and if not will it definitely burn my coral.
 

Phyl

Officer Emeritus
Officer Emeritus
You *might* find the far right and left fringe to be a little dark depending on the reflector used, but if the fixture is meant for a 36" tank then I'd say it will likely look fine. (Conventional "wisdom" is that 1MH bulb will throw light in a 2'x2' square.) As far as whether or not it will be "enough" light I would say that is plenty of wattage to grow just about anything you'd care to keep.

If you're increasing light over existing corals then it is best to phase that in. As you add corals to any system you always need to take into consideration the lighting they're coming from and what they're going to and start them off in the tank (low, high, etc) depending on whether they're going to be under more light or less light than the light they were coming from.

If your fixture uses Double Ended bulbs then it is critical that the UV shield that came with the fixture be in place between the lamp and the corals.
 
I have a 250 over my 30 gallon and it is more than enough light, your tank is 6" deeper and 6" wider front to back. With the right reflector you should be OK. You need UV protection on DE bulbs, Se bulbs have it built into the Glass of the bulb itself.
 
my fixture came with a piece of glass where the bulb sits. How do I know this is going to filter the light. Does any glass act as a filter.
 
My old SeaStar PrismPendant had a regular SE MH bulb and came with a glass shield. I stopped using it because I was tired of cleaning it and I found I got around 5% more light without it. It did keep heat out of the tank a little better though.
 
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