Some tips for the future:
Air circulation inside the case doesn't matter if you have enough air going through it. These extra fans you bought ought to be installed one low and one high for intake and output. If you just blow around the same air it doesn't do anything.
This has however worked in your favour. By supplying mainly blue during the first week(s) of flowering you suppressed the natural tendency of the plant to stretch. Do that in future too if you want to keep them short. The more blue light in the first 2-3 weeks of flower, the shorter they stay. I think you did observe a nice stretch when you did eventually switch spectrum.
Don't flush, at least not the way it's commonly understood. And also don't feed just water once you start with fertilizer.. that's flushing. Once you start to introduce fertilizers you best keep that level as steady as possible. So don't go water one day and fertilizer the other.. go average strength on both days.
Soil and fertilizer are a fickle combo, check out coco.
When defoliating.. aim for the leaves, unless your goal is to clear out the bottom for air circulation purposes. I've seen you top branches on multiple occasions and also take off tiny leaves. Go top to bottom and only trim the ones that are shading out lower growth.
Additionally you want to remove the leaves completely (gentgrasp the plant above the leaf and then remove it by pulling down close to the stem). Any bit of petiole you leave standing is a possible source for mold.
