Another lighting question of course

[Jeraljay]

I have a 81 g tank, I am setting up for a reef. Dimension are 53LX24HX14W I am want to use a MH system. I have heard 3-5 watts per gallon is good? what is best for a Reef, optimal?

 

[ellisz]

WPG is not a real good measure for a reef tank. A 5ft tank is somewhat different. A MH light normally covers 2ft of area. Most people get 2 MH's for a 4ft tank. I almost bought a 5ft 100 gal and plannined on using my 4ft fixture(2x250 MH + 2x54 T5). I know a guy that uses 2x400MH w/ VHO actinic on a 125 and it looks nice. A 2x250 is about all I can handle on my 75 gal due to the heat it generates.

 

[AndyH5512]

5 WPG should cover anything you may want in there, including clams. I have a 120, and I am at 4.67 WPG and my clams are doing fine. I have been told that it's not just the WPG, but how well the light penetrates into the water, which I believe.

 

[Jeraljay]

I almost bought a 5ft 100 gal and plannined on using my 4ft fixture(2x250 MH + 2x54 T5). .

SO how does that work you run the MH during the day and the T5 at night. And BTW what is a T5

 

[fishrfreinds]

T-5 is 5/8 diameter bulb that is High output Floerscent. A 4 ft. bulb produces 54 watts

 

[fishrfreinds]

and you never really run any lights during the night except moon lights, you know to give that nice night time feeling.