Plants Drooping, curling and some Yellowing,

I have 8 plants, in 6x6 roockwool cubes. Plants are 18-24" tall. They are about 8 weeks old and everything was going fine until the started drooping and curling. Kinda claw like. this is my 1st grow and Im lost. Please help.

Ive been hand watering 1-2 times a day depending on how dry the cube felt. Ive been using pureblend pro grow 1 tbsp per gal and cal mag 1 tsp per gal of mountain spring water. ph is between 5.8-6.8. temp is 78 and humidity is 45-50%.

Any and all advice would help!! Thanks!

i think the problem might be
overwatering
i dont think humidity is the problem 45-50%
is pretty good
also u may want to transplant them to a bigger
pot so the roots have more room to grow
hope i was helpful

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http://www.weedbay.net/overgrow-thebook/PlantTrouble/Merged.htm

1.https://www.rollitup.org/marijuana-plant-problems/132382-deficency-nute-burn-diagnostic.html

2.http://www.icmag.com/ic/showthread.php?t=11688

3.http://www.weedbay.net/overgrow-thebook/default.htm

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ure pots are too small 6x6x6? too small for 2ft plants... are the leaves limp? or are they stiffer like they would be if healthy?

should I get rockwool slabs to put the cubes on so I can get more root growth?

i use soil and they work s fine and very cheap my man

Try adding a teaspoon of h2o2 to your water.