New growth turning light green

[mtnman2016]

I've been trying to figure out what is causing this, I've never encountered it before. I am using Roots Organic soil and just started feeding with Fox Farms 7 days ago when I saw this start, figuring they were calling out for nutes. That feeding was at 50%. I decided to do 100% 4 days later trying to turn it around but it doesn't seem to be helping.

It appears to be an immobile nutrient issue like a sulfur deficiency since it is only affecting new growth. Today I used straight water with cal-mag to see if that will help.

I have 3 plants in Roots Organic all doing the same but I have 1 plant in Ocean Forest and it looks perfect and it hasn't had any nutrients yet.

The environment and watering is:
72-76 degrees
40-45% RH
Tap water PH'd to 6.4-6.7
LED's 16" above canopy
Grow Big & Big Bloom nutes so far

Anyone ever seen this before and know what is causing it?

 

[OneMoreRip]

Do you know the ec of feeding?

it’s been a while for me but I thought I used lower ph using salt nutes in soil but don’t quote me on that. May want to check fox farms website and see if it has any information that could help you.

 

[mtnman2016]

Do you know the ec of feeding?

it’s been a while for me but I thought I used lower ph using salt nutes in soil but don’t quote me on that. May want to check fox farms website and see if it has any information that could help you.

Ya, I have been using the same nutes for years and same ph range for years. I usually use RO water and cal-mag as well though, this time it's tap water. This time around is sort of an experiment.

As far as ppm I got a reading of ~700 but can't remember which feeding that was.

When I looked this morning, they appear to start turning around so I have to think they were very hungry and maybe the cal-mag I fed yesterday helped. I believe with full nute regiment and cal-mag from time to time all will be fine.

Thanks for the response.

 

[mtnman2016]

For those that see this this in a search, the trick was to add calmag every other watering an increase flower nutes. I was stressing way too soon LOL. Peace...