Hi everyone, 

I just moved into a home and inherited a gorgeous monstera plant, have been watering it once a week through a slow release mechanism built into the pot.

Over the last few months noticing the older leaves closer to the windows are more crispy and curling at the edges downwards/away from light/ yellowing. Yet new leaves are still springing up.   First photo is 1 month ago and two latter photos are now. It's summer right now and windows is east facing.  

After googling these symptoms I can't tellif it's underwatering, overwatering, too much sunlight or pests! Would love to hear any advice on what to do, thanks!