As mentioned in the title. The color at the edges of this leaf is much lighter than that of the center of the leaf. It almost looks like the color is draining out of the plant, or receding away from the edges. The surrounding leaves look OK, it's just this one leaf that seems to be affected.
How I care for the plant:
- I keep this plant out of direct sunlight.
- I water it with 75ml of distilled water every 8 days, letting it drain out the bottom of the pot.
- I'm not currently mixing fertilizer into the water, since I've read that this should happen only during the growing months (it's currently February).
- I keep the temperature in the room around 60 degrees.
My plant care app says this might be a case of anthracnose, but the photos it provides don't seem to match what I observe on my plant leaf.