[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: Lighting in my hood and ballast factors

... If I use t-8's that are 30 watts I will need a lot of lights for my 
tanks. I have a 140
gallon and if I use 2 (is that even enough) watts per gallon that would
mean that I need [140x2]/30=9.33 t-8 bulbs....

In terms of light output, 32W 4' T-8 tubes are about the same as 40W 4' 
T-12's.  I would guess that the watts per gallon rule-of-thumb you're using 
was developed with T-12's, so you may want to adjust accordingly.

I hope I'm not repeating someone else's comment here, but for people looking 
to get more light out of their fluorescents, you might try driving them with 
a ballast that has a higher ballast factor.  The ballast factor is one of 
the numbers by which a ballast is rated.  It indicates how much light a tube 
will produce, relative to its rated output, when driven by that ballast. 
 So, if a T-8 rated at 3000 initial lumens is driven by a ballast with a 
ballast factor of 1.20, it will produce about 3600 initial lumens.  Of 
course the ballast will consume more electricity as well.  (There are also 
ballasts with ballast factors less than 1.0, if anyone is interested.)  Oh 
yeah, even if you want to have just the rated light output, you should check 
the ballast factor of the ballast you buy, just to make sure you get what 
you wanted.  Hope this is helpful.

Thanks to all the experienced aquatic plant keeping folks who contribute to 
this digest and make it so helpful to beginners like me.

Wade Shimoda
Honolulu, HI