What is the issue with these leaves?

Hello everyone. Ive seen a lot of issues in my days but never these markings.

Only thing I've added new is the mini split. My day temps are between 73° and 75° with a RH around the 50% Mark give or take. Before I added the mini split my temps were in the low to mid and sometimes high 80s. So I ran lights at 50% and pounded them with air to keep it somewhat cool. I run 4 air cooled 1000s. The strain is a Gorilla Glue cross. 7 gallon pots. Promix. Sensi bloom as a base with rhino skin, and bud candy right now. I'm 2 days into flowering of course.

The night temp was down to 68° in the room the other night so I wonder if it's a shock from the cool air?

Only 3 or 4 plants have these leaves with these issues and it's only large fan leaves and only about 15-20% of the large fan leaves on the few particular plants.

Any ideas?

A few more pics

please confirm your sensi nutes

part A 3-0-0 NPK
part B 1-2-6 NPK

how are you mxing the fertilizer
how many mls per gallon and how often do you fertilizer vs plain water?


it looks like a magnesium issue...my guess is lock out
could be related to too much K if your over doing it on the rhino or bud candy which im betting is the issue

for bloom id mix part A 6mls per gallon part B 10 mls per gallon

its hard to suggest the right amount of calmag and Epsom salt because they don't list the % amounts on the bottles (or do they?)
but Id start somewhere around 2mls per gallon calmag and 1/4 tsp Epsom salt each time you fertilize mixing it with the part A and B

dump the bud candy it adds too much K.. it says it has magnesium but we have no idea how much cuz it doesn't list it

use the rhino every 3rd or fourth watering and use it sparingly (maybe 5mls per gallon)

its the only way to get the K down
you really don't want to lower the K by using less of the part B because it carries all your micro nutes, theres no K in the part A

adding the bud candy and rhino which both contain K is just pushing it way up... the part B already has plenty of K by itself

Very good info!

I feed once every 4 or 5 days and each plant gets approximately a gallon and a half of water. For feeding I take the recommended dosage and cut it all in half.

So I will skip the rhino for the next few waters and greatly decrease the bud candy and see what happens.

Also I feed every water. I add 6 ml per gallon of A and B and 3 ml per gallon of all additives.

id also add 1/4 tsp Epsom salt to your feeds

I ran your nutes thru a nutrient calculator so I think if you mix it the way I suggested youll be happy

the rate I recommended might be less than what your used to feeding so you might need to feed every other watering with my mix suggestion

ok that helps

that's a pretty light feed

and based on your mix it doesn't look like your too high on K like I first said

your just magnesium def so 1/4 tsp Epsom per gallon on the regular should be good

you can top dress with 1/2 tsp a couple times to catch up and or foliar feed 1/2 tsp per gallon

id seriously consider raising the part B to 10mls or your micro nutes will be low and it might eventually lead to iron def depending on whats in the soil..plus its the only source of P which runs low in your mix
then dump the bud candy or use it rarely

I will do. Just plain Epson? I've never used it before.

Jeffro420 said:

I will do. Just plain Epson? I've never used it before.

Click to expand...

yup

Epsom is magnesium sulfate

don't get the ones with the lavender or whatever ... just plain Epsom salt

the rates I suggested are low and very safe

no danger