I have a 1200GPH pump
 

Ron, How do you feel about using smooth textured lava rock for a hydroponic growing medium? I have a 1200GPH pump, can I use this monster for a 20 plant 1" system or will it blow my veggies out of the 2-litter bottles? Will placing several several over flow fittings in the system slow down the water flow? Thank you for this informative website.

All you can do is give it a try with smooth lava rock. Never tried ether. I think you can redirect as much as need be and with that size pump you won't have to put an air stone in your reservoir because the redirected flow will create plenty of bubbles.