I don't remember the capacity dimensions but the tub measures 19 inches across, by 39.5 inches long, and is 6 inches deep. The theory behind the single tub is to get a bit more root space than I would have had in individual containers within the same space. Granted, the container IS shallower than I would have liked, but by growing all the plants in there together, I hope that the reduced depth won't be a great hindrance.
Secondly FF, yes they will go the distance in that tub. I plan to start bending them before too long. Once the LST gets started, I'll force them to grow horizontally right under the light. Hopefully I'll end up with a bunch of loooong, delicious, colas!!