I am posting an updated video on the "Lettuce and Basil in Fill and Drain (Ebb and Flow System)" thread on this forum.

I went with CNS 17 for the nutes as it calculated out as very economical over several cycles.

I also took some online advice and moved the nutrient change out to 3 weeks instead of 2. That was good advice as IâÂÂm a couple days shy of the 3 weeks, and they are only now showing signs of no2 weakness. And that is only very small signs.

I am using the nutrients at half strength as they have been in the hydro system since 1 November and germinated a week or so before that.. When I change the solution, I will up it to full strength as the growth is now very heavy.

Here is the vid. http://www.youtube.com/watch?v=9ObpoFxEPxU

My blog outlining the project from the beginning is at the link below.

Here is a link that might be useful: Hydroponic ebb and flow system blog

Great website! With your system is the air-stone really necessary? Wouldn't the water and roots be oxygenated enough with just the ebb and flow movement? What type of timer do you use with your system? I've been planning on using a DWC setup but I do have an old pond pump that should work with a system like this. Would I see much of a difference between dwc and ebb and flow?

I should use half strength nutes for the first three weeks and then switch to full strength. I've been looking at cns 17, wish they sold it in half-gallons. I guess I'll go for the full gallon of the grow formula. Best price I've seen is 22.95/gal

I grow my lettuce with waste water or whatever is lying around, have used soil nutrients like miricle grow in the past (with added epsom salts) and they grew fine, I have personally given up grown lettuce to maturity and now just grow baby lettuce. I just have a layer of spreader mat, a inch or so of clay pallets and a dripper that is gravity feed.

Lettuce really is a low requirement plant, heck you could just about piss in a bucket of hard water and they would grow.

I've been growing lettuce for nine months in 3- 36"x16"x6" high Sterlite containers. In two, I have 2 each open, weighted down air tubes. In the other one I have 2 air stones. If anything, the container with the air stones has been a little less productive. Not very scientific, but interesting.

Mark

bbrush, why have you given up on raising full grown lettuce?

what lights would be best for growing lettuce? I'm thinking flourescent lights will work fine. What is the most efficient option here?

I think the most efficient (initial cost, bulb replacement, elctrical usage) option for lettuce is shoplights with T8 6500k bulbs. Watch for sales or rebates on the shoplights. You should be able to get the 2 bulb, 48 inch T8 lights for around $6 after rebates. The bulbs are about 2 bucks each. At 32W each, they use little electricity.

I understand T5 systems are more efficient to run, but the initial outlay is more and the bulbs are more expensive to replace. I believe T5 is the way to go when I need to add red spectrum to the mix for more flowering type plants such as tomatoes or peppers.

Hope that helps a bit.

I just prefer to eat baby lettuce plus it is expensive here while lettuce heads are cheap, plus that system above gives me more room in my other systems to grow other crops. Metal Halide would be the best I would think, not the most efficient mind you.

bbrush,

I did a study last spring looking at the cost of mols of light per watt (initial cost was not included). I included "shop lights," HPS, CFL and MH. (Sidenote: a mol is a defined amount of PAR light emitted over a defined time period.)

The MH kicked butts!

Mike

I know that lighting is not my area, but just wanted to point out that lettuces is a plant with low light requirements. Even though MH and HPS lights put out the best light, from what I've read it's to strong for good lettuces (unless maybe it's far away, or in low wattage). And that lettuces actually do better in low light than they do in strong light. Although I don't know, maybe there are some specific variety's that prefer strong light.

hh,

I think you are correct about lettuce and light. I always grow it under a sheet or Reemay if it is outside, inside it was just in a south facing window.

I;m wondering if the basil was getting too much light? It started out great but as it grew, the top leaves started yellowing a bit. Last evening, I topped all the plants so I should see in a few days if that was a problem.

Mike

So how much light would you recommend? The space is about 18" by 6 - 7ft. I'm planning on lining the sides and top with aluminum foil to reflect light back onto the plants. With this being and odd shaped area I'm guessing I'll have to have some overlap with the light fixtures. If I get two 48" double bulb T8 fixtures. Will that provide enough light for a 7 ft by 18 inch area? I realize the fixtures would overlap by a foot. Also, can anyone recommend good T8 fixtures? I don't mind paying a little extra for decent quality, or ordering them. I just want some that will last more than a couple months.