Leaves are light green

The Problem is the calmag you cant do anything about a calmag Defizite its because of the led lights and if you add more calmag the ph in the soil will change and everything will become even whorse

I agree with Papa T. The water from the dehumidifier has no minerals in it and if you are not adding those minerals in another way you are going to run into exactly what you have here. You can add all sorts of rock dust and buy minerals, or you could just use tap water which has most of what the plant needs in it. It's too early for the fade to be setting in like this, so you definitely have a lot of deficiency issues, but is almost too late to fix them.

If she is almost done the leaves will loose their color. The plant will take what it needs from the leaves.

I just read your diary. Man you gotta stop using your dehumidifier water for watering your plants. That’s just a no go in my books.