Help with halides and power compact placement

[xboxhacker]

I built a canopy for my 55 gallon glass tank. The canopy is 16 tall. On the top i mounted a 250 watt halide and 4 pcs. 2 actnic o3 and 2 10000k daylight. Is this to high for the powercompacts ? The pc fixture i gutted was a current. they are 65 watt bulbs. Should I shorten the whole canopy? Should I try to drop pcs a little lower. I built it tall as i was worried about heat. The tank doesnt appear as bright as it used to even with the halides. ANY inout would be great. TIA Shawn

[clsanchez77]

That is way too high IMO.

The MH fixtures should prob be around 6-9 off the water and the PC should be about 3" off the water.

A physics note, the intensity of a light source is based on the inverse square law...such that dropping the distance between the center of the bulb to the surface of the water by half will multiply the light intensity fourfold.

Chris

[dc_909]

Too high

[xboxhacker]

I will drop he canopy to 7 inches from water. What fans can you reccomend? I figure i need alot of flow to dissipate the heat from 2 halides and the pcs. Also what direction should i set the fans ie.. the flow direction. thanks again for all your help. You guys are great. shawn

[slavearm]

Cheap 120mm computer fans and a cheap 12v powersupply. Panaflo fans are pretty quiet for their CFM

[dc_909]

Have both fans blow into the canopy. I have a coralife fan which works for me. IceCap has a more expensive one that turns on when it needs to. I just have mine on the same timer as my halides.

[xboxhacker]

so 2 fans on 1 side? or 1 fan on each side blowing into canopy?

[dc_909]

I have one on each side, but you can always have multiple fans on each side if you need to.