Hey Pal.
So, I've had this issue many many times. And only thing I can put it down to is a bad mix. (Different nutrients not working well together in the same space)
If you are going to give dif enzymes and just dif nutrients in general it's best to space them out and give 1 set 1 week and 1 the other. With a decent water feed inbetween. This is the only thing that it can be. With it been so bad (so much rust) it is just a bad mix of nutrients. Your plant is doing well. And looks like whatever the issue was. It has come out the other side. If it was gonna get worse, your leafs would be in a much worse state. It is bad. But, I'm nearly sure you coming out the other side of it. Good luck
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