Brian - Thanks for the awesome response. I am still undecided on growing media. I am trying to get whatever I can locally (Home Depot, Ace Hardware, Orchard Supply, Tractor Supply Co), and sometimes they just don't have what I'm looking for. I think the lava rock is no longer an option for me. It's between pea gravel, river rock, expanded shale, or Hydroton if I feel like giving myself a minor heart attack in the wallet department.

Let me ask you this. With your pH problems you've had.....is it a constant battle, or does it eventually get down to a steady level without you needing to add anything to it for buffering it?

I went out and purchased my grow beds and fish tank yesterday....WOOHOO! I think I am not going with a CHIFT PIST system, only because I don't have the room nor space to raise the tank above the grow beds for feeding them. Since the tank is going to be UNDER the beds, I have decided to initially create this system the old fashion way.

When the time comes to move the setup to a larger space, then I think I will go with a larger tank in that kind of setup.