gmslave, that is exactly it. Only once they grew 30 inches in 2 weeks. Middle of the way up. The new growth looks fine, but it's only when the plant ages, I am currently watering 2400ml in 11000ml pots. I was reading your other posts about this and was thinking this was happening to me as well. I'm preparing a flush now and make sure I saturate everything from here on out. Thanks.