least amount of wattage

[js_bass]

what is the least amount of wattage or type of light to have with a reef tank that has hard corals and such ?

[dc_909]

T5s

[js_bass]

thanks, what is vho lighting?

[pjf]

A T12-VHO fluorescent tube for your 90-gallon tank will be 1-1/2" in diameter (12/8"), 4-feet long, consume 115 watts and produce 49 to 55 lumens per watt (http://www.elliptipar.com/vertical/Vertpdf/VertGdLg.pdf) for a total of about 6000 lumens.

A 4-foot 54-watt T5-HO is 5/8" in diameter and produces 93 lumens per watt (http://www.lrc.rpi.edu/programs/nlpip/lightingAnswers/lat5/pc1a.asp) for a total of about 5000 lumens.

Although the T12-VHO consumes twice the electrical power, it barely exceeds the light output of the T5-HO. The T5-HO will probably direct more light into your tank because its thinner diameter will block less light that bounces off the reflector.

For energy efficiency, I recommend the T5-HO.

Those who favor VHO are touting only one VHO bulb and that is UV Lighting's "Super Actinic R" that is reputedly the "best" bulb for bringing out coral fluorescence. Some aquarists use both T5HO and VHO bulbs. Keep in mind that T5 bulbs are about 2-inches shorter than VHO bulbs and do not have compatible pins. In a hood, they will need different sockets, switches and ballasts.