It only says that because a plant that small is succeptible to shocks and changes. I read that your soil does have nutes, but I've never used that brand.
Sorry, that pic tells me nothing.
Try PH neutral rockwool or Oasis instead, is my suggestion.
From that pic it looks lke they were moved to large pots?
How large? If they're in 2 gallon pots that you only water occassionally, chances are they're still getting drowned.

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