Doc , mites can ruin a whole crop in a matter of weeks or even days if conditions are just right , it is better to deal with them as soon as you find them.
The best way to deal with infestations is prevention , I spray with an insecticide once a week , about a 1/4 second spray into the oscilating fan that blows over my plants , then I shut the door on my way out , I have never had any pest problem.
A 1/4 second spray once a week adds up to a 3 second spray over a 12 week grow period , not too toxic in my opinon.
As for that weird plant of yours , sometimes there is just no reason for it , some plants just grow weird , sometimes it can even work to your advantage , I had one that grew virtually no leaves , just some little tiny purple ones.
I let it grow and it eventually produced almost 1/2 pound of nice bud , If i can find a pic of it I will post it and show you.
Another thing I have found with the hempy's , the water in the resevoir can become stagnant after a while , I will let them dry out occasionally (maybe every two weeks) , just until the plant almost starts to wilt , then overfill with pure water once before starting with the nutes again.
Either that or overfill them every time so that lots of runoff comes out the drain holes , that effectively flushes them , that way uses lots of water though and I try to keep my humidity down so the first way works best for me.
Your grow is looking good dude.
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