New to Rollitup. Plant problems. Pale/yellowish bunched new growth and some other problems

Hi there. I am using
terra pro plus soil
6x240w LEDs
25L fabric pots
AN Sensi grow base nutes
Some Organic cal mag
Hygrozyme
Root excelurator
Temps between 25-27.5c day
21-23 night

I am aware I had some light burn that started and then nutrient burn. I cut back and went half dose on this feed. Its easy to get carried away sometimes.

SO this problem has really stumped me.. I've had it a few times now and it's pretty much being happening throughout veg on this grow and the one before. I'm doing multiple strains they all have it. Some worse some not so bad.
Growth does not seem to be slowing at all from it,
And once the leaves have grown out they seem to be fine apart from the bit of damage on the odd leaf as seen in pictures

Also I forgot to mention this seems to be happening on the new growth below the tops as well although not as obvious as the tops.
The plants are growing very fast and at first I put it down to that but something tells me this is not quite right. I have raised the lights as I think they was getting too close but because its happening on all new growth I think it is also something else.. I have tried to diagnose but I can't put my. Finger on one thing. So any help would be absolutely,, greatly appreciated. Thank you!

Whats the PPM of the feed?

What is the pH running? (I know but it's not always "pH Perfect" lol)

Also, medium pH. You need to test for that as well. I have had many issues with medium pH crashing. With Sunshine I had trouble with it being too alkaline after they changed peat suppliers.

Renfro said:

Also, medium pH. You need to test for that as well. I have had many issues with medium pH crashing. With Sunshine I had trouble with it being too alkaline after they changed peat suppliers.

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I've had trouble trying to calibrate my bluelab ph pen, it will calibrate to 7 but not 4 .. To be honest I gave up with it, I read that someone contacted AN and they assured as long as ph is between 4 and 9 roughly the nutrients will be up taken. I haven't ppmed my feed as I know from last time how much is needed from the stages of growth although I clearly overdone it at some point(probably 2 feeds ago I went a bit heavy)
But I would have expected stunted growth if it was bad. the reason I didn't use the ppm meter is because it was in different unit and converting it was a nightmare because there was 3 different types of ppm..or ec. I forget.
American and two others ‍
I think ill give a feed of 1ml per litre next feed and just to ph the water and see what happens. I was meant to switch to flower today but I'm hesitant, although growth has not slowed at all, what do you think?

Ajh19921 said:

the reason I didn't use the ppm meter is because it was in different unit and converting it was a nightmare because there was 3 different types of ppm..or ec. I forget.

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Bluelab Truncheon

Ajh19921 said:

contacted AN and they assured as long as ph is between 4 and 9 roughly the nutrients will be up taken

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lmao

I can't help you.

It is simple. Either you aren't feeding strong enough or the pH is limiting uptake. Those are the most likely causes aside from potentially root rot from poor watering practices.

pH DOES matter. You were fed a bunch of hog wash.

That's all I got for ya really. pH DOES matter.

Renfro said:

Bluelab Truncheon

lmao

I can't help you.

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I know ph should be around 6.5.. That's what I have aimed for but now I can't get the pH pen to calibrate to 4.

Renfro said:

It is simple. Either you aren't feeding strong enough or the pH is limiting uptake. Those are the most likely causes aside from potentially root rot from poor watering practices.

pH DOES matter. You were fed a bunch of hog wash.

That's all I got for ya really. pH DOES matter.

Click to expand...

It's definitely not root rot I understand the wet dry cycle and I seen the roots on the last up pot. Very good.
Thank you for your input. I need to look at these two potential problems then, probably going with the pH one as I've been unable to work that damn pen.. Nightmare.

TBH I have generally only calibrated my pen at 7 and it's works fine compared to my apera.

I have seen this happen when someone is feeding say 700 PPM and simply raising the PPM to 1000 fixed it (these PPMs are at 0.5 scale). I have also seen it happen when the pH was too high in the medium. A good soil pH pen like the blue lab or apera PH60S is the way to find out and they both work in liquid as well.