My first hydro experience

[Wanwan]

Hello to everyone!
I just discovered this site and I hope we can find a solution to my problem.
I'm growing in hydro for the first time, I don't have much experience. I share with you my problem, which I consider as a lack of nutrients. I would appreciate it if someone who is an expert on this could help me out.
briefly features;
-4x super lemon haze photoperiod
- 3rd week of flowering
-hydro r-dwc 4x20lt (DIY)
-ph 6.1
-temperature 28-24
-resorvior temperature 19
-humidity 40
-light 600w hps
- nutrients
a) floramicro 0.9ml/lt
b) floragroe 0.7ml/lt
c)florabloom 1.6ml/lt
d) cal-mag 0.5ml/lt
-airpump 60lt/munite

 

[Chow13]

To me it looks like PH swings. How often do you test. When is the last time you have calibrated your PH meter?
PH is everything with hydro. If it goes out of range for 1h you can have symptoms for a few days. I use 2 cheap pens and when they loose sync or I switch from veg to bloom I calibrate both of them. New batteries at the start of every grow.

Lack of nuturents is possible. You need to be testing your EC/PPM to know that. If EC is going down then you increase your feed and if its going up then you decrease or dilute your feed. If you can go with a pen that does EC because PPM has different measurement scales.
For example this is true 1.0EC = 500ppm = 650ppm = 700 ppm( https://hydro-gardens.com/ec-to-tds-conversion/ )

 

[Wanwan]

To me it looks like PH swings. How often do you test. When is the last time you have calibrated your PH meter?
PH is everything with hydro. If it goes out of range for 1h you can have symptoms for a few days. I use 2 cheap pens and when they loose sync or I switch from veg to bloom I calibrate both of them. New batteries at the start of every grow.

Lack of nuturents is possible. You need to be testing your EC/PPM to know that. If EC is going down then you increase your feed and if its going up then you decrease or dilute your feed. If you can go with a pen that does EC because PPM has different measurement scales.
For example this is true 1.0EC = 500ppm = 650ppm = 700 ppm( https://hydro-gardens.com/ec-to-tds-conversion/ )

Thank you for your answer. I check the pH twice a day and calibrate it daily so I'm pretty sure there is no pH fluctuation. I can say that he usually drinks a lot of water because of high temperature and low humidity, so ppm increase is seen, I fix the ppm with additional water supplement. But I still can't find what the problem is. Could the nutrient be spoiled?