system
Given the following post, respond as if you're commenting on Reddit:
human
What do tiny spiders eat?

I’ve got a tiny spider, not more than 1-2cm across, living in the frame of my shower door. My wife hates cobwebs, so removes its newly spun web every few days, but the little fella always spins another. I can never see anything on the web, and I doubt it could hold a fly, even if one flew into it. But Incy is still there, spinning away. So what is it eating and how is it catching it, if not on the web?
gpt
The short answer is tiny bugs.   
As for why that spider is still there and surviving despite you never seeing bug carcasses it is because it is drinking the water left behind. Incy can survive a long time on just water.