brown and yellow spots...HELP PLEASE

[g.man]

anyways, im starting to notice my leaves curling downwards and some of the leaves are even starting to fold up and over on the edged. theres some yellowish/brown spots on the leaves but all their roots look healthy. WHAT AM I SUPPOSED TO DO??? t hey were started in rapid rooter coco plugs then transplanted into the ebb n flow table. im using advanced sensi gro n bloom two part ph perfect nutrients with RO water. the ph in my res was at like 4.3 last night when i checked it and the ppm was around 810. i qtr'd the reccomended dosage and fed last wednesday. when i talked to customer service at advanced i was told its probably an uptake problem and i should turn my lights off then use a spray bottle with 1ml/gallon of nutes and foliar feed them then wait an hr and tuen the lights back on. the temp in the res stays between 65 and 69 and the room temps between 76 and 80. this is my first hydro grow and i'd love any tips tricks or pointers anyone has on how i can fix these bad girls. please help

 

[g.man]

am i overwatering? is it nute burn? a nitrogen deficiency? should i change out the res with plain ph'd RO water and hope that corrects it? please help me

 

[namvet25]

I'm not a hydro guy but you might be giving them to strong of a nute dose.They are to small so I would clean your res out and use plain ph waterunti they get bigger than use a light dose at first then work your way up.Check our hydro forum for more help.

 

[g.man]

thanks namvet25. i plan on changing out the water in the res with RO water after work and watching them closely over the next cpl days. i will post pics along the way and make sure to keep you updated. anyone else have suggestions???

 

[A4]

Dude, 810 w/ RO? I am no hydro guy either but I can tell you that 810 seems waaaaaay too high for that young of a plant. Everything I have read about hydro in the past seems to be around 75-150 ppm at that age. Maybe someone with some more experience will chime in but I gotta believe 810 is through the roof, especially if it is an Auto.

 

[g.man]

i changed the res with fresh RO water (ph 6.8) last night. the ppm was at 13. after i ran it through a cycle, the ph went down to 4.4 and the ppm was up to 220. seeing as i had already run a low dosage of nutes through my systembefore the res change, do you think this is my reason for increased ppm? also, im assuming the hydroton is a buffer of some sort because the ph went down so much? please correct me if im wrong tho. there is new growth (3rd or 4th set of true leaves) on the babies but its all very small. as of right now its only the first set of leaves on a few plants that have spots and discoloration. could i still salvage them with just the first set being damaged?

i also spoke with a rep for advanced nutrients last night and he said when using the sensi gro and bloom ph perfect nutes, that ppm doesnt matter. i was told if i follow the standard ppm measurements for the age of my plants that i will be underfeeding them. i dont know how true this is but thats what i was told. he also said that there are organic nutrients and that there is no exact way to measure the EC of organics so that could cause the reading to be high. im sure im forgetting more but ill be checking the thread via phone and ill get on the computer when i can and keep updating this but until then PLEASE keep the helpful info coming in

 

[A4]

My best guess, and it is just a guess, there were enough residual nutes in your media and such to push your ppm up and ph down. That wouldn't be surprising.

New growth is good, the leaf damage that is done is done. There is no repairing that but if you have new growth that looks good it is a plus.

As for the nutrients and what the rep stated, I have no idea. Look at this link and read what OOOGaUTo says. He seems to have used these before. https://www.autoflower.org/f44/questions-about-advanced-nutrient-feedings-19212.html