I've got the cheapest method. I use 1/2gal,1gal and large coffee containers. I fill them with crushed lime rock(rinsed of course). I use dual air pumps and a 5way air splitter on each line from the pump, they cost $12.00 at walmart, $2.00 for 8ft air tubing and $4.00 for each air splitter. I use 400watt light on a light mover rail. I get 1-3 oz per/baby. My lights cost $20.00ea/month. Thats a harvest of 10 babies a month.