I used two plastic bins. The first is filled 1/2 inch with rocks, the second is filled completely with rocks. I elevated the second one using some bricks and tilted it a bit toward the other bin. I added a few holes to the second bin so that the water would drain out.
I have a pump in the lower bin that pumps water to the top bin. I have this pump on a timer which runs for 1/2 hour 4 times a day, spaced evenly. The lights are 2 compact florescent bulbs which I leave on all day.
Any feed back on timing of the lights and pumps would be appreciated. Looking to make a better system later this week.
Here is the better system I made: Mike's Second Aqauponics System