So I have 4 plants, and every one is starting to show some black/dark brown tips on the majority of the leaves (new and old). The colouring starts at the end of the leaf tips. and the tips on the edges are now starting to change colour too, working its way down the leaves. Some of the plants are experiencing this worse than others. This damage is worse near the top half of the plant with old and new foliage experiencing it. The end of some of the leaves (1/2") start to curl down and the black tips then curl back up (1/16")

ladies are 1 month old from seed. lights on 18 hrs, then off 6. While lights are on, temp is 70-75. watering starts when lights turn. I water every 3 hrs, for 7 mins each, using 1L/hr drippers. Growing in rockwool. Following the ultimate feeding program. every watering session consists of the following nutes per gallon: 5ml GH Flora Micro, 10ml GH Flora Gro, 3ml GH Flora Bloom, 4ml Green Planet Aussie, and 1 cap/10gal of Zyme. Reservoir is 15gal. Nutes are drained back into the reservoir. pH stays between 5.7 - 6.0. The air is replaced every few mins, and have a couple fans for circulation. Humidity is between 40-50%

any suggestions?
sickNstoned Reviewed by sickNstoned on . Dark Tips on Corners. Why? with pics So I have 4 plants, and every one is starting to show some black/dark brown tips on the majority of the leaves (new and old). The colouring starts at the end of the leaf tips. and the tips on the edges are now starting to change colour too, working its way down the leaves. Some of the plants are experiencing this worse than others. This damage is worse near the top half of the plant with old and new foliage experiencing it. The end of some of the leaves (1/2") start to curl down and the black Rating: 5