Help with my babies please!

Hi everyone, I hope to solve my problem here this thing is acting quickly unfortunately.
I am growing Sweet Cheese autoflowering from Sweet Seeds in a homemade hydro system DWC made of 10 gallons container with 2 plants each constantly in 7 gallons water. Each container has 2 bubblers and the air pump is on 24/7 and can manage a 200 gal container easily.
Babies are at around day 20 on a 18-6 schedule.
2x250w hps with cooltube.
Water Temp 23-24C (73-75F)
Room Temp 22C night, 27C day

I have noticed the ph is going up from 5.5-5.6 to 6.0-6.3 in 3 days.
i am using Dutch Pro Grow at around half strenght 1.2 ml per liter with a ppm 480-500
1 ml per liter of Canna Mono trace mix
0.3 ml per liter House&Garden roots Excelulator
1 ml per liter of Voodoo juice from Advanced Nutrients.

I can't figure out the exact problem because from the pics around here sometimes looks Calcium deficiency and other times Boron.
I am pretty unsure and for this reason I'll be more than thankful for help.

Thanks to all in advance!!!!

Looks like it might be some powder mold and heat stress. How far are the lights from the canopy? Also, the fluctuation of pH is likely causing some stress, though I will ask for more of us to give some input.

keysareme said:

Looks like it might be some powder mold and heat stress. How far are the lights from the canopy? Also, the fluctuation of pH is likely causing some stress, though I will ask for more of us to give some input.

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Lights are at around 9 inches from the top of the plants.
Do you know any pH stabilizers products please?

Thanks a lot

keysareme said:

Looks like it might be some powder mold and heat stress. How far are the lights from the canopy? Also, the fluctuation of pH is likely causing some stress, though I will ask for more of us to give some input.

Click to expand...

Hi again. I did have a check on my plants and pics on the web and doesn't look powder mold hopefully!!!

Plants are to young to feed so much with those amounts, sings of "n" burn, flush for 1 week then start to feed at a rate of 1/4 what is directed Generally amounts on the containers are to strong for regular growers and are for commerical grows. Your PH is ok for that strain

harris hawk said:

Plants are to young to feed so much with those amounts, sings of "n" burn, flush for 1 week then start to feed at a rate of 1/4 what is directed Generally amounts on the containers are to strong for regular growers and are for commerical grows. Your PH is ok for that strain

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Hello, I did what you said. I will see what will happen now. The problem is also that in Dutch Pro bottle there isn't the amount of nutes nor in their website. I did half strength I will half it as soon as my plants will be back on track. Thanks!

Hi everyone, just an update! I have been lucky it wasn't a nutrient burn. My doses were quite low. Checking pics on google images I found a guy with my same problem. It was Cal (mostly) and Mag deficiency. It was burning the inside of the leaves towards the outside with brown spots till the necrosis (if I can call it this way) of the leaf.
That guy also found problems on the roots getting brown. I didn't have this problem! After adding an half strenght cal-mag ( brand: Plant magic) I have solved the problem. Now my Sweet Cheese is doing great already into flowering after 4 weeks. Fingers crossed....