effecient lighting for a 31 in deep tank..

[sgolden]

i have a pair of 400w mh , i also have 175w mh...even with good reflectors is 175 enough?...i would like to avoid the heat and save on electric... share your thoughts?

 

[james3370]

depends on what you want to keep at the bottom. that 175 is only gonna get good penetration to about 18-24" deep or so (depending on how high you mount it off the water)

 

[turtleman9100]

I have 30 inch tanks. I lit mine with 250 DE icecap ballast and xm bulbs. I keep some sps, softies and lps. Everything stayed healthy, full of color but slow growth. I switched to 400 watt mogul base and its hit and miss. You will either quickly bleach coral and have to move them around or you will finally satisfy light hungry coral and notice a quicker growth rate. 175's are out of the question IMO for a 31 inch deep tank.