These instructions are brought to you after six months of successful growing. Ingrid had been growing for a year by the time I gave it a try.
I've also attached a PDF file of one of Dr. Kratky's papers outlining his method and how it works... if you want to get all "sciency."
Step 1: What you'll need
Plastic paint primer and paint
1/2 inch x 1/2 inch elbow (optional)
Rubber grommet 3/4 inch OD x 7/16 inch ID (optional)
Clear vinyl tubing 1/2 inch OD x 3/8 inch ID (optional)
1/2 inch drill bit (optional)
2 inch hole saw
8 - 2 inch net cups per lettuce bed.
Strap to hold shape of container once it's filled with water
PH water testing kit
Hydroponic nutrient (your choice of brand)
Place to set up your lettuce beds
This setup should come in at under $30