bubbleponic questions?

well i have been doing some research and it seems like everyone that says stealth hydro works has no pics or anything to back it up. also a lot of people are saying not to buy this system so it has really turned me off of buying it. maybe diy is the way to go but i just have some questions if anyone can help. well my first question is if i get a 20 gallon tub what size air pump and airstones will i need and how much water do you put in it. is there any step by step guide to growing in a small closet i need a system that can hold at least four plants!!! pease help

18 gallon rubbermaid would be fine.
Enuff air to make ur water frothy.On the box when u buy pumps get one compatible to 150-200 gallon size or more. They sell a whisper 6 out let pump at petsmart for like 24 bux that will work! but always have a back up pump putting air in ur tub.

Here are some pix of that same setup and what to expect