This plant seems to be suffering from a general lack of nutrition and this may be linked to using that organic fertilizer with the clay balls, as that fertilizers seems to be specifically designed for use with soil. I would be adding a complete liquid fertilizer, probably in a 50-50 ratio of both grow and bloom fertilizers in combination.
If you are restricted in which products you can use for the competition, it certainly is not a good advertisement for the product in question.
Perhaps by only using 25 grams of the fertilizer, you have used nowhere near enough.
Cheers, Organoman.