how big to cut 2 liter bottles

[Rey]

Hi, my name is Rey and I have a ? I down loaded a Picture of a 11 plant, do it yourself hydroponic
system from your page, but it doesn't tell me how big to cut 2 liter bottles, what size pump I need,
how do you keep plants from falling over as they grow. I'm new at this, and I really want to start
soon. Any info. you can give me will help. The stuff I got from your page has been wonderful so far,
but I need more. Please help
Rey