i find the ones i use at lowes and so far ive had Really good macro growth. I use them on the night cycle; on at 7pm 0ff at 7am
I use the,**Bright Effects Daylight 90-Watt Replacement PAR38 CFL Outdoor Flood** I use these on my 2 29gal sump with built in fuges
Item #: 75224 Model: 60066
Uses only 26 Watts
Uses 71% less energy and lasts 8 times as long as standard bulbs
Lasts 8,000 hours, up to 5 years
Use for outdoor security and stake light fixtures
6500K color temperature
Provides cool, natural light
I think these run about $9each
I also have these on my 20 gallon dedicated refugium
Bright Effects Daylight 65-Watt Replacement R30 CFL Indoor Flood Bulb
Item #: 296879 Model: 60063
Uses only 15 WattsUses 77% less energy and lasts 8 times as long as standard bulbs
Lasts 8,000 hours, up to 5 years
Use for indoor track and recessed can fixtures
6500K color temperature
Provides cool, natural light
and these run about $7each
I use them in one of the cheap Lowes
Bayco 8-1/2" Clamp Light with Aluminum Reflector i think these are like $8
The bulbs do stick out past the dome a little all i do is fit a piece of
egg crate grating to the opening (i buy that at lowes or Home Depot but i havent found the bulb at HD) Then i figure out where the light has to go and cut out a piece of the egg crate about 5"x5" so the bulb will fit into the opening and it lets the reflector sit flat, and thats it about $20 or so and 5-10 minutes time i have a fuge light. Hope it helps Hopefully the link works.
Bright Effects at Lowe's: Daylight 90-Watt Replacement PAR38 CFL Outdoor Flood 1-Pack