Added more light but is it enough?
 

I thought my 15w t5 wasn't enough light for my phals in my indoor greenhouse since it barely registered on my momet meter thingie...so I bought this ViaVolt and added it but it STILL barely registers. It a 15w and a 24w not enough? Here's a picture of my indoor greenhouse (old pic, only shows the 15w) so you guys can see what I'm talking about.

How wide and deep is the "greenhouse"? A single 2' T5 HO lamp with a good reflector is usually pretty good for an area roughly 30" x 12"; without a reflector, you are really only getting a small portion of the light output doing any good.

I actually measured the intensity of a Hydrofarm 2' T5 with-, and without its reflector, and saw this:

http://www.firstrays.com/Pictures/reflector.jpg

In fact the '0" from the reflector' point was actually 1" from the bulb, but you can see 1) the effect of the reflector, and 2) how rapidly the light intensity drops off with distance.

I was hoping someone as knowledgeable as you world answer, thanks Ray! I'll measure it and post the numbers later.

I just measured it at around 1.5 ft deep, 4 ft long, and 4ft tall.