Thank you to everyone who responded to my "10 gallon Planning Ahead" thread.
Today while walking though Walmart I came across these for $7 - 2 20w 6500k u-tube CFL's.

I figured that the shape is straight and curved like the other more expensive CFL that most retro kits use, so that these would be much better than the spiral with less light loss.
So above a 10 gallon, with some DIY reflectors, out of the 40w total watts could I expect at least 30-35 watts?
Also, the two sockets on my stock hood are made for 25w or less incandescent. Although these are 20w taking the place of 75w, would these be safe to use since the output is 20w?
Today while walking though Walmart I came across these for $7 - 2 20w 6500k u-tube CFL's.

I figured that the shape is straight and curved like the other more expensive CFL that most retro kits use, so that these would be much better than the spiral with less light loss.
So above a 10 gallon, with some DIY reflectors, out of the 40w total watts could I expect at least 30-35 watts?
Also, the two sockets on my stock hood are made for 25w or less incandescent. Although these are 20w taking the place of 75w, would these be safe to use since the output is 20w?