sounds like you can get a nice tub in there.
I say upwards to 8-9 flowering females,
with some LST and SCROG that can help.
Good luck.
I say Hps is a all-around healthy spectrum
for MJ.
250-400 watt will get you some nice buds
the 400watter will just make your nugs denser,
the 250 does a great job.