if you vent through your ceiling go buy ducting and take it to the end walls of most house have vents or straight to the peak were there should be ridge vents in roof that would be better then just going in open space in attic also some roofs have the spinning cone thing that also would work good
there all farly stiff you what the kind they use out west for plant irragation if you live wheres its hot or dry home depot or lowes will carry it just notice your from cali they should have it at the store or landscaping place
they say you need time for air for the roots to take up but i made one that ran a 1/4 inch line 24/7bottom of bucket hole in it with another 1/2 hose running back to res with air stone in res and they grow good and fast no problems
mistake i seen that once so i tred it bad decion on my part plant never really recovered bad bad yeld should of just through it out after it because it never recover from it
go with soil till you can figure it out also take a clone from the plant in soil so you can learn how to clone and use that one in dwc and see if you can grow both of them and see which grow method you perfer and if you should fail at one you have a back up
miine were raised run off back to res and but there was allways about 1 inch of water in bottom of bucket depends on were you drill your holes little water is good incase of pump failer and it seemed to work good intill ran out off hieght do to only 6 and half ceilings because i like big plants