Metal Halide Reflector Question

[jcnkt_ellis]

I have 2x 250w Mogul MH fixtures with spiderlight reflectors positioned about 9-10 inches from the waters surface on a 48x24x30 (150g tall) tank. Currently I am seeing growth on my montis that are high up on the rock work, about 12" from the surface and on my lps and softies on the sandbed. If I wanted to place a clam on the sandbed, or even just generally improve the available light in the tank, should I replace the spiderlight reflectors with Lumen Brights or another similar pendant style? I'm not wanting to grow SPS on the sandbed but I want enough light for possibly a clam, or at the very least, my plate, acan, lobo, and zoas to have good growth. Any suggestions from others with deep tanks is greatly appreciated.

If necessary for a clear answer, I am using 2 magenta/4??nm blue 48" ecoxotic stunners with reflectors for supplemental light and nothing else.

[BSJF]

What kind of clam?

[jcnkt_ellis]

Maxima...don't have room on the sand bed for anything larger

[alton]

On my 200 I had 3 x 250w MH and spider reflectors in a canopy. On my 300 I have the same MH but use Lumenbright minis. Lets just say if you are using MH and spider reflectors you are wasting energy. I have an average PAR level of 250 on the sand.

[jcnkt_ellis]

Thanks alton, that's what I thought from the research I had finally done.

[koa25]

After recently upgrading to Lumenbright reflectors from spider reflectors. I can say i will never go with cheap reflectors. I have not tested my par values yet. But the spread and quality of light i am getting is a million times better.