Well, it's been a quiet several weeks. I attended the UVI International Aquaponics & Aquaculture course in mid March and have been back 3 weeks.
Here are my notes from March 25, which was my first day back at the farm since my last entry:
AP system notes
ph readings show 6.8 consistently
Plants are mixed. Some are pale, some are green. A lettuce I did not have much hope for went to seed but also was richly green. Fed it to the fish.
Based on the UVI Aquaponics system, I added chelated iron to 2 mg/liter. This took 250ml of my liquid chelated iron solution.
Added 1/2 teaspoon of Potassium. Based it on instructions on package of 1-2 kilos per hectare and proportioned it down.
Applied a foliar spray of potassium. Diluted 5 ml into 2 liters and applied to leaves. Dumped unsprayed amount into system at mineralization tank.
Note: on my phone instructions, Carlitos added a tuna-tin sized amount of builder's lye to the system last week, for bringing calcium up. Though the fish feed already has some, UVI says add more.
I'll check ph first thing tomorrow. It may go up do to the K and Ca.
Planted chives, 16 lettuces (starters purhased at store - yes I cheated), cilantro, parsley, celery, one medium sized chile plant. Threw out most or all of the brocoli started 2 weeks ago. I don't think those plants would have made it in any system really. Divided the chives and cilantro between gravel and raft systems. All the letuce went into the raft sysem. Everything else went into gravel.
Almost everything greened up right away after adding the iron, calcium and potassium. The only thing that didn't were two watermelon plants in the raft system. The ones panted in gravel did react positively.
The following are three video updates, about a week apart each. Each video goes from plant to plant in the same order. You should be able to notice plant growth and other differences from video to video.