I have been growing for a long time and it seems of late I cant get anything to go right in my room.
My current grow is 4 plants under 4 600w HID's in 50 L pots. Temps in the room are nominal around the 26 degree C mark and humidity is about 23% They are in Cocos and receive one feed a day for 1 min which is keeping the medium damp but not wet.
I have been having trouble with leaves yellowing and curling up (The Claw) and I have tried everything I know to keep them going but seem to be losing the fight. I would like to know if it is a deficiency or if I need to water more? I thought initially I was over watering so I backed off for a few days after flushing the pots with clean water but this didn't seem to help. There is also some salinity on the top soil which I have not seen before so don't know what to make of it.
I have included some pics and any help would be appreciated