too much light?

[reefermike1]

i have an 18tall aga tank that i plan to set up as a nano (sps, clams)i plan to run with no sump(stand is to small to hold anything worth anything) probly do a cpr hot skimmer and i have a fluval 305 (210gph) that ill use for charcoal and flow. lighting is my concern looking at a coralife 150w mh 14k that attaches to rim of the tank. would that be too much? the tank is only 20" long so i dont see any pc lighting that i would want because 24" seems to be the minimum for any kind of wattage that ive seen. tank dimensions are 20lx10wx20h

edit. current usa has a couple 20"pc units i was looking at a 1x40w dual daytime actinic and a 2x40w, just trying to get the best lighting for sps, clams, anenomoe. so how many watts should i have in an 18 gallon without it being overkill?

[mdcorcoran]

It's about 8.3 watts/gallon. I don't think that would be a problem. You might have to adjust the height though.

[wharyat]

The height of the tank, and the dominant corals chosen are the primary determinates as to what type and how much lighting you need.

@ 20" high with a maxima or crocea clam a 175watt MH would do wonders. Just keeping SPS you could get by with a 70watt MH or an intense fluorescent array.


For comparison my 20g has a 175 watt 10kK MH and 2 65w 50/50 pcs, corals and clams grow like crazy. About 1" monthly for sps, 1/8-1/4" monthly on a maxima.

[Wiskey]

That is not too much light for SPS, over my SPS 15G tank I had a 250W XM 10K and 2*32W PC's.

If you think about it, what is the difference between a nano with a 400W MH, and a coral at the very top of a 120G tank with 2, 400W MH?

Whiskey

[jberd]

You are right whiskey it does not matter the amount of gallons in the tank it is the depth at which the corals are from the surface of the water. As light travels down the water colum it quickley depletes in intesity. I have a 150 hqi and 2 65 wat pc on my 37 an it is all about placement. Everything is doing great.

[storrisch]

Coralife does make a 20" 1x96watt quad 50/50 fixture. Marineandreef.com has killer prices on lighting fixtures. The best I have ever seen. They even beat my prices from my work (at the LFS.) They have it on there for 87.00.

[pledosophy]

My 150 HQI does great over my 20g long.

[jenajet]

You could do a hanging mh pendant as well.