T5HO bulb and reflector question?

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Aquarium Advice Addict
May 14, 2009
New York
Hi All
I have what I think is a straight forward question. How far should the T5HO bulb sit above the reflector?
If you got a retrofit kit, the reflector should clip onto the endcaps...at least that's how the IceCap kits work. The bulb sits almost totally inside the reflector. There is maybe a 1" gap between the bulb and reflector.
The bulb is supposed to sit at the focal point of the reflector, that is where the max amount of light will be reflected out to the tank.

The exact point depends on the shape of the reflector. But most should have clips or other mounting hardware that position it correctly on the endcaps.
I read your reply and re-adjusted the reflectors after work fired it up and noticed a difference, there is more light being directed downwards. Thanks for the info Larry.
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