In my experience, you don't want to give the moms too many lumens unless you plan on trimming a lot. I have a 200w cfl, 12,000 lumens, for a little mom & clones in a 4sq ft box and I could scale that down to probably half. I'd say 2000-4000 lumens per square foot should be a good range. The point is to keep the mom healthy and growing but not vigorously growing, & the clones/seedlings don't need too much light at first. I think you could use 4 or 5 of those t12's for the mom & kids, as long as your mother doesn't get too tall or you keep the canopy the only growing part.