If you are going with FO
and will not be adding LR
or interested in changing from FO
in the future you could use xenon lamps - Actually Xenon lamps are in reality a Metal Halide based lamp. Xenon is a gas added to the lamp (similar to Mecury added to a Flourescent bulb) to provide usable light during the MH
warm-up time (standard MH
's typically use argon which heats up more slowly.
Xenon bulbs come in a variety of applications but generally they have considerable filteration which narrows their bandwidth thereby limiting their spectrum. This is done because most HID
lamps have considerable output in the UV
range and xenon bulbs are no exception - however, being that they are either used pointing directly at some one (headlight) or directly at living space these harmful rays (wavelengths) are removed. In aquaruim lighting these wavelengths are retained as they are the wavelengths which many marine organisms thrive in.
The good news is that Xenon HID
lamp temperatures are typically about 6500 K
- which is solidly in the acceptable range for Marine organisms though not likely optimum. They also provide a hi CRI and therfore have a wide spectrum less the UV
and near UV