put those lamps as close as 1"-2" from the plants, if you can.

any photos of the first crop before harvest? They look like they were well on thier way. I"ve been able to get a pound of bud from a 3' x 4' x 4' space. I stuff as many as 12 plants in there. Trim off all the lower branches that won't be getting the light later on in the grow. You can do it. Good Luck.