Question regarding number of supplemental CFLs w/ 250HPS

First time poster with a quick question. I am going to be starting a new grow, 2 girls, in a space thats im guessing is around 6Hx3Lx4W and i was curious about supplemental CFLs at the bases of the girls to reach areas the 250HPS doesnt penetrate.

Ive found at home depot/lowes/walmart 23w (100w equivalents) in the 6500k range for about 10$ for a 4 pack. I was curious if these would be enough or am i better off purchasing some higher equivalents online...ive seen some 42s, etc. Also, if the 23w will be sufficient, how many would be ideal 4 or 6?

Thanks guys! Been a while since ive done this and last time i had the luxury of a 400w HPS so this wasnt a concern!

Personally, I would use 42 watters, as they tend to be very efficient. But 23 watters are good too, because they are cheaper and easier to find at your local stores.
As far as using them with your 250 HPS, use as many cfl's as you can fit in your cabinet. The more light the better.
And don't forget, for flowering 2700k is ideal, although 6500k will work too.

any suggestions on fixtures for the CFLs? ive been lookin at home depot and lowes for "vanity" bathroom sets with 3 or 4 spots for CFLs....although i did notice a max of 60W per base, and i was looking to use splitters to get 2 lights per base...not sure if thats a good idea with those cheap units