Lots of lettuce and iron deficiency

Quick update. Here it is my aquaponics system in August. The bottom image is just after a trim. As you can see, we’ve got lots of lettuce…this is enough for many days of salads.
I noticed a bit of yellowing that was obviously an iron deficiency, so I added some chelated iron to the system. Less than a teaspoon did the trick. They greened up really quickly after that…just a few days or so.
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2013-08-27-07-38-32
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