Hi markmahlum,

I am in a bit of a rush, but here are some quick numbers.

Example pump: Elite 799
1.5 WATTS * 24 hours * rate (say $0.11/KWH) = about 4 cents a day.

I used this in a 15X24 inch container with about 4inches of water.

24 inch Sun blaster light: (24hours a day for the first 2 weeks.)
24 WATTS * 24 hours * rate (say $0.11/KWH) = about 63 cents a day.

Um I donÂt know who did my math this morning, but It should have been:
1.5 WATTS * 24 hours / 1000 * rate (say $0.11/KWH) = about 0.4 cents a day.
24 WATTS * 24 hours / 1000 * rate (say $0.11/KWH) = about 6.3 cents a day

Thanks postma. I have exceptional sunlight here at 7400' in SW Colorado so I hope artificial light won't be necessary. I am set up on a rate watchers plan with the local electric company. 14 cents on peak, 3 1/2 cents off peak.

Mark

Mark,
I don't know much about electricity costs, but I can help you out everywhere else. Depending on the variety of lettuce, you need at least 8-12" square inches per plant. In a hydroponic setup, especially in a raft system, 24/7 aeration is key. The more oxygen you provide to the water, the better your plants will grow. It keeps the nutrient rich water from going stagnant and the beneficial bacteria happy and growing. In addition, the plants roots need oxygen to grow and stay healthy.