SOIL Is this a Sign of light burn any input is appreciated

[Shankemdirty]

So This is my First time with my new light i plan on getting P3 P3IP4400, Kill A Watt Electricity Usage Monitor to check how much watts i am pushing out cause the dimmer dial it's really hard to tell beyond 50% I recently turned the knob up a little from 50% to maybe 60% to 70% these plants are 5 weeks old from seedling my old lights we're not that powerful so i never had to worry about it.

Something else might be going on as well tho.

These pictures are of 2 plants that look like are close to same issue 1 girl scout cookies and 1 gorilla glue i also noticed one leaf messed up a little not sure if it was a defect or a bug praying its not a bug lol

 

[PeterMatanzas]

Not light burn, it’s a nutrient deficiency, maybe magnesium. What’s your watering pH? I suspect the nutrients she needs are present but the plant can’t access because of pH lockout

 

[Shankemdirty]

I have always Done 6.5ph should i be going for 6.0 cause my Soil is similar to coco it's Pro-Mix High Porosity Peat Growing Medium pretty sure it has SPHAGNUM PEAT MOSS thanks for the response

 

[Rwise]

What is the soil PH, and the run off water PH? BTW Peat is acidic, can be as low as 3.3, great for blueberries.

 

[PeterMatanzas]

I have always Done 6.5ph

mix it up instead, go with 6.2 next, then 6.2 again, 6.1 then 6.3 -> and this problem will disappear imo.

you can do 6.5 but that's the ceiling and you do need to mix up the pH's of your watering.

 

[MuskieMan]

I also use Pro Mix HP, If I were you I would check the drainage from your pots. I water with a PH of 6.1 and the drainage comes out at PH of 6.6. I think this is what caused me some problems with the early part of my grow until I figured it out... Good Luck

 

[Shankemdirty]

So my run off ph is about a 5.5 and it does look like my plants are not eating as much as the run off ppm was 1500ppm they receive near 1200ppm every other watering do you guys think i should flush i need to kick these suckers into flowering within the week as they are getting to my desired height is it worth to flush and just mix in my flowering nutes.

 

[Shankemdirty]

Here is some update photos now i finally got my P3 P3IP4400, Kill A Watt Electricity Usage Monitor and what i found out is that the half indent on the knob that i thought was half way was actually 465 watts out of 600 watts and that pushing it above that which i thought was 70% was actually 90% pushing around 578 watts now that was not expected so i think the yellowing is due to the light being near max at 90%

I am using HLG 600 RSPEC so that is a very powerful light for my 48"48"80" grow tent at 90% i reverted it back to the stable 465 watts that i had it on for the past month with stable results i never wanted to push the light that hard during veg so glad i got the p3 to calculate the % of the lights output.

The top of the plants are yellowish and they been in the taco state but i think it is cause of the lights these pictures compared to the first pictures are about 5 days apart as you can see they have shown the deficiency better.

Is it safe to push these guys into flower and give a flush there is the possibility that i need to adjust My Base nutrients as i am doing custom amounts week by week with the General Hydroponics Flora Trio
as i am trying to figure a spreadsheet with a certain amount out each week adding more each week it has been green sails up till the start of week 6

The Plants Just started the 7th week of Veg