So I was just thinking about your issue in the shower and thought of two possible things.

#1: Your temp. ok so your temps are the most recommended because your plants can utilize more lumens with out worry of burning and things like spider mite populations are kept to a minimum when you drop the temps at night. Bacteria populations are also kept to a minimum when you drop your temps at night. Bacteria thrives at about 85 degrees for the most part. Your sugar which really only helps your plants via feeding the bacteria could be overloaded as your populations of benificial bacteria can not get to prime with the drop which should be taken into effect when trying to raise the brix factor with sugar. Remember plants store starch for food (produced in the blue spectrum of light) which later breaks down into sugar when needed (yellow spectrum. This is why MHs are better for grow cycles) The transpiration could have drawn the highly solvable sugar into the plants which may inturn effect the phospholipid bilayer of the cells that make up and aid in necessary functions of your plant. In short you may not want to use sugar daddy.

#2
Your soil could have a bacteria that is not beneficial. The added sugar will aid in manifesting this to levels that are not so good for your plant though I would think not so much with the temps your running. Sugars may increase the likelyhood of rusts, blights, molds and unbenifical fungi which sometimes resemble cal defs or lockup.

In either case you may wish to consider cutting your kids off from sweets.
I enjoy using earthjuice grow, bloom and maxicrop dry flakes. Thrive alive green is great though test out different levels to see what you like. I run everything low which may not be optimal for harvests though in top for quality. When I started professionally years ago some one who had been doing it professionally for years told me some thing I am going to pass on to you. Whether you follow it is up to you. When it comes to all that crazy additives, keep it simple. Best of luck.

one love
c
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