You have a 29 gallon reef tank right? Well if it where me and I had the space I would use at least one (probably both cause I love corals) ten gallon as a frag tank. 40 watts would be good for a wide range of corals. I love mushrooms so I would be cutting away, and everything else grows so fast. I also read a topic on reef central about how multiple lighting schedules would increase growth in corals (but it would really stress any fish) so when I setup a frag tank it will be 6 hours on 6 hours off then 6 on and 6 off w/o fish.