How much light over a 100 gal for sps?

[Pomme]

How much light over a 100 gal for sps?

At the moment i have a 100 gal tank with a 250 watt halide over it, the tank is a weird shape by being 40" wide by 24" deep by 28" high.

I am going to add some more 250 watt compact metal halide units, at least two. As this would give me 750 watt over the tank.

But i am wondering how many of these compact 250 unit you suggest i add?

Andrew

[Reefland]

Hi Andrew,

What exactly do you mean by compact MH units?

Typically, a MH covers about 2'x2' square so over your tank, I would go with 2 units.

Scott Z.

[Pomme]

hi scott.

Here is the lighting i have and the tank 6 months ago:




and here is a picture of the compact units:

STM compact 250 watt Metal Halide
A unique STM product that is small compact and very powerful. The unit combines a remote head unit, with an optimised reflector and a remote ballast for easy installing into small locations like tank hoods. The optimised reflector design allows the maximum output to be achieved from the lamp. The unit offers a 40" spread at 10" above the water. Ideal for many situations where powerful but compact unit is required.

A note of caution this unit is extremly powerful the computer optimised reflector allows the greatest output from the bulb. Customers are advised to aclimatise corals to this light level as even when corals have been kept under 250 watt lighting from less efficient units burning and light shock can occur. We recommend halving the light cycle during the aclimatisation period. Once the corals are fully adapted back to a more natural level of light you will find increased growth and colouration.

We can wholly recommed this lamp for use with acropora and sps corals.
Unit is available in white. Dimensions 8"x6"x6"

Includes fixing bracket

As i cant ift in any more pendants iam going to make a beem between the two bars which go up and hold the pendant at the moment and then attach the new halides to the beem.

But my light at the moment has a good relector as the corals (sps) are growing each end of the tank, but some corals have browned out and have shown no signs of change so i have decided to add some more light, which will be the compact units.

But i am wondering how many to add?