Indoor Grow Lab ?a

Hi....I have just a few year experience at indoor growing for that being said I'm now where near being a Pro. So here is what I have invested in over the years... I have a 2 feet wide by 2 feet long by 5 feet tall Grow Lab with the lighting of a 150 Watt H.P.S lamp. This lamp is small but it's my little start up lamp. well I grow in Ocean Forest soil in 5 gallon pot usually. but i wanted to do the Mother Plant thing and try out to get some cuttings and do a Sea Of Green method a try this time around. What size pot and how many can i fit in this tent of mines? I was thinking of doing the 12/12 light schedule after the seeding sprout out. Before with the two plants in my last grow I had did everything the same to them from seedlings but at the end one plant always seems to get taller than the other and then they reach up to almost the 45 feet length of the tent. Can I get some suggestions and what I can do with what I have available. Thanks!