O.K., 5 X 3 X 41/2,,, dont get 1000 watts unless you have great,,no,no,,,, excellent ventilation, Hmmm, well after further though,(and Im no pro at this) I would get a 400 watt hps and mh conversion,, its cheap for startin out and youll get a very good yield and its cheap,, theres a place called HTG Supply.com that has the whole setup very cheap,,,, just a suggestion as Im sure there will be other people on here with other suggestions, so just take it all in and decide,, I have got the same set up and I think you would be happy, so good luck on your quest and make sure you read the growfaq at the top of the page,,