From Lowes or Home depot... Philips EcoSmart 100W Equivalent Daylight (6500K) Compact Fluorescent. Comes in several flavors of compact, dimmable etc and cheap. Grows Chaeto like mad (perfect color temp). Think 4 pack is like $13, long life and low power consumption. I use that and a $10 gooseneck fixture with clamp and reflector from Lowes. I give away, throw away Chaeto by the pounds.