need some help setting up a reverse photoperiod system in my sump

[VIC]

Fellow reefers,
I am attempting to set up a reverse photoperiod system in my 100 gallon sump. Due to my calcium reactor bringing down my ph,(8.20-8.00) I am setting up 3 150 watt metal halides over the sump that will run on 8 hour intervals, (24hrs). I was thinking about adding alot of calerpa which will attatch to the 150lbs of live rock in the sump.
For those of you who run a similiar system..What kinds of calerpa work best and how much should I purchase? Also, any ideas on where to purchase this would help. Any input on setting this up is appreciated.
Thanks,
Vic

[Ninong]

Check this out: http://www.homestead.com/spasse/

Ninong

[chromis]

Well, if you have anything to trade I have plenty of Cauperla Racemosa to spare. Or, if you just want to pay overnight shipping. I came back from MACNA and found that the C. Racemosa in my refugium had over doubled in size. A very fast grower and very hardy. I could also send you some sargassum. email me if interested.

Andrew