Well Martin on a tank that size you can probably get away with one halide light. At that depth a 250w would probably give you your most vestatility.
Another idea is to use 2x175w lamps over the 3 foot span and you will get quite a bit of overlaping of the 2 lights which would probably be great as well.
There are may options as you know.
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No matter what the morrow brings, inventors keep inventing things.
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Jonathan
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