What are the growing conditions it's in? And what about the soil and your watering? How long did you have it before the problem became apparent?

It's in an office. The soil is regular potting soil and it was doing well until about 2 months ago. I have a dish of water next to it for more humidity. I water once a week on Fridays.

The reason I was asking how long you had it before the problem became apparent is because soil doesn't stay the same. It breaks down over time. The organic matter disappears and you're left with a denser/heavier soil that usually doesn't drain as well and isn't sufficiently aerated. Repotting it into better soil might help. With watering it's best to do it when the plant needs it rather than on a fixed time schedule. That would mean checking it more frequently. Office air is usually fairly dry but the plant should be okay over a weekend when no one is around.

Thank you. I will try re-potting it.

There are some insects glued on that insect trap glue pad. Do you know what these are?

When grown as house plants these are susceptible to low humidity, excessive fertilizer, hard water and fluoride in water. Search web with botanical name Calathea lancifolia for additional guidance.

It looks it looks like it might be bacterial leaf spot.

Deanna

How do I treat that? Or can I?

A fungicide with copper in it.

Valeriev--how is your plant? Mine has developed the same problems since I recently repotted it in 5-1-1 mix. I plan to start using rain water. I don't really want to go out and buy a fungicide.

Ohhh. Poor thing died. I couldn't get it back to life.

Oh dear, I hope I can keep mine alive.

Causes browning

...after 4 years... what?