nice 150w pendent vs. 250w fixture

[Lundy24]

Im in the planning stages for a 30 gal oceanic cube. To not limit what u keep most people seem to think a 250w is needed since the tank is 21" tall. I am trying to minimize energy consumption and was thinking a nice 150w pendent w/electronic ballast, lumanmax 3 or lumanarc mini, would be comparable in light output to a 250w fixute with a less efficient reflector, like a sunpod. The tank dimensions are 20x18x21. LMK what you think.

Here are links to some of my options

ocean light
http://www.marinedepot.com/aquarium_lighting_metal_halide_aqua_medic_ocean_lights.asp?CartId=

sunpod
http://www.marinedepot.com/md_viewItem.asp?idproduct=CU01160

lumanmax
http://www.marinedepot.com/md_viewItem.asp?idproduct=SL1531

 

[aninjaatemyshoe]

You only need to worry about the height if you plan on putting demanding SPS/clams on the bottom. Even then you probably would be fine with a high PAR bulb and good reflector. I think a decent 150W fixture will be more than fine for you. The Pheonix 14K is a good bulb for PAR and color. Go with the lumanmax of the 3 that you listed.

Want a really effective 150W MH? Try the 6500K PAR Iwasaki. It is basically a metal halide in a flood light and it screws into a mogul socket. Better than many 250W in terms of PAR. You're probably going to want to supplement it with actinic T5 or VHO, however, as it is kinda on the yellow side of things.

 

[Lundy24]

Im planning on keeping a couple crocea clams, will there be any problems keeping them with the 150w?