if you want
acros ... i would go for a 175w or 250w
MH over the 70w or even 2x70w
MHs. i would go for the 250w personally. it sounds like a lot, but in all reality ... it is only 8.62 watts per gallon (bad way to estimate it). a BC29,
IIRC, is a fairly tall tank ... the 250w will penetrate it very nicely.
