I am considering making a MH fixture to replace my 320W of PC lighting. The corner is a pie shape, 34x34 with a 34" radius front, see attached drawing. Would a single 400w fixture be sufficient as far as spread goes if I had it far enough above the tank? Thanks for the help.
Help with DIY MH for 92 corner
- Thread starter bstollmaier
- Start date
You could get two 250watt fixtures and you would probably get a lot better coverage.
techie note, converting images from bmp to jpeg can help folks with slow connections a lot.
techie note, converting images from bmp to jpeg can help folks with slow connections a lot.
Thanks. Yeah, I'm trying to not break the bank and was hoping the 1 400W would cover enough, especially if it was up high enough. Would the intensity be noticably greater than the 320W of PC I currently have? (1/2 actinic, 1/2 10,000)
How tall is the tank? (Sorry, my math skills aren't working all that well at the moment when it comes to figuring out the dimensions / volume of an irregular shape.)
In short, yes, a 400w MH will provide more intensity than 320w of PC. There are factors that ultimately influence that though (bulb, reflector, ballast, height off the water).
The more you raise a MH off the top of the water, the less intensity is reaching the bottom of the tank. Yes, a single MH could be raised high enough to cover that entire tank (more or less), but the amount of light reaching the lower portions of the tank would be small and defeat the purpose of having a MH set-up. Also, there would likely be a noticeably amount of light spill over -- the MH would be lighting the walls and floor around the tank, too.
Generally speaking, a single MH provides roughly 24" x 24" of coverage. For a tank under 24" tall, 250w MHs (or less depending on actual height) are commonly used. For a tank deeper than 24", 400w MHs come more into play.
In short, yes, a 400w MH will provide more intensity than 320w of PC. There are factors that ultimately influence that though (bulb, reflector, ballast, height off the water).
The more you raise a MH off the top of the water, the less intensity is reaching the bottom of the tank. Yes, a single MH could be raised high enough to cover that entire tank (more or less), but the amount of light reaching the lower portions of the tank would be small and defeat the purpose of having a MH set-up. Also, there would likely be a noticeably amount of light spill over -- the MH would be lighting the walls and floor around the tank, too.
Generally speaking, a single MH provides roughly 24" x 24" of coverage. For a tank under 24" tall, 250w MHs (or less depending on actual height) are commonly used. For a tank deeper than 24", 400w MHs come more into play.
The tank is 24" deep. I figured if I built a big enough reflector, it would hold most of the light over the footprint.
Even with a custom reflector, I'm not sure how effective one MH would be. It's likely there would still be heavily shaded areas in the tank, but that might be something that can be worked around when aquascaping. A somewhat unconventional rockwork design might lead to it being successful. Or, if you really like some of the non-photosynthetic corals, they could be placed in the darker areas of the tank. It really depends what your goals are for the tank.
