[carym]

For lighting it depends on what you are fragging, but at 12" high you could probably get by with T5 light for just about everything. As far as lighting the Chaeto that would be more standard light or plant lighting, you do plan on reverse lighting it correct? Also, one thought why do a sand bed in the main frag tank when you will have a DSB in the refugium? I would think it would be easier to vacumn the deterius and debris if you don't do a sand bed in the main tank and also with the sand you will need better lights because it will assorb the light.