Yellow spots on leaves

ph is fuked, nutes dont burn, lack of food causes burning, either by not using enough or the ph is off or using to much food and this causes ph to drop. anyways you look at it burns are from lack of food
you need to feed more than 2 times a day for 5 min each.

Having a hard time keeping ph between 5.5 and 5.8 ... ppm drop not extreme which led me to believe that they werent getting enough to eat but others tell me my solution is too strong. I'm making solution as recommended. BC Northern Lights tells me that 5 min twice a day is sufficient when roots are in resevoir... so confused!

im no hydro guy but i see others feed like 15 min each hour. dont believe all recipes on bottles, they alway always tell us to use more. a plant will only intake what it needs.
using a rez will constantly need to be ph`d again over n over as the food is taken up by the plant. my opinion here is the interveinal diss-colouration is a ph imballance from up n down in the ph. will lock it up eventualy. if that was my plant at that size id be feeding at about 600 to 800 ppm. and 5.5 ph.