I am running an RDWC, I believe some of my plants are suffering from an Iron deficiency. I am running a full dose of General Hydroponics Flora Series, so there is Iron present, I believe that it is not being absorbed due to hot temps. My question, is what is the best way to give them Iron. I can not find a foliar feed. It seems that Cal-Mag is the only thing out there. Even if I buy the Cal-Mag, how will it help if the plants can't absorb the Iron that is available?
Iron can be attracted to your water pump if it a magnetic-drive pump. This can potentially pull enough iron from your solution to cause a deficiency. I have never had an issue with it but a friend of mine did, so he added some "Add 2.7" by Dutch Master which supplements iron and that seemed to do the trick.