Dwc System In two 30 gal Tubs

Hey everyone. I am new to this. I am setting up a dwc system using two 30 gallon tubs. I hope to have 6 plants in each one. I am running 3 6" airstones with each system. I have done some reading but i am coming back to the same problem. How will i ever be able to drain these huge tubs and refill them with already ph'd water. Somebody please help! I will be using a 600w hps and the room im using is a walk in closet 8' by 4' with 8 ft ceilings. Any help is welcome.

I'd see about maybe getting shallower tubs, or you will be going through a hell of a lot of water. Having an RO system would be the best way to go imo.

you could buy a cheap sump pupmp to drain them with... running a hose to your tub... as for filling . just keep and extra tub to mix new res water in and pump it back... because if you wanna Do DWC the bigger the roots the bigger the buds right.