Calathea rapidly declining
Hello,
I am relatively new to the houseplant world and bought this calathea in April (she was already a tall plant). Up to now I had no real issues with her, appart from a few crispy tips and my cat playing with a few of her leaves. I noticed her growth was a bit slow (new leaves were small and rare) at the beginning of summer so I repotted in regular soil with a lot of perlite, a little bit of leca and started fertilizer (npk 7-3-6). I bottom water with brita-filtered water only and keep her near my bathroom so she gets humidity from the shower. Fertilizer is diluted and once every other watering. She gets light from a big west-facing window.
In the last week or two her leaves started curling, browning and drying very fast. I’ve already had to remove a few of them. I have not changed her watering habits (only when pot feels light and top is dry) and cannot figure out what is wrong. Somehow she is now producing new growth (???) while the rest of her seems to be dying. I’m afraid it is pests but haven’t seen any bugs on her. Maybe it’s too much fertilizer?
What could be the problem?? How do I help her?
Cat tax at the end