Can Pets Stress Out Fish

I have pet rats and am planning on setting up my tank to start cycling soon. I sometimes let my rats onto my desk (where the tank will be) and was wondering if the rats would stress out the fish? It seems like a dumb question but I’m genuinely curious how fish react to other small pets. I’d be really interested to see what stories others have as well!

 

It shouldn't stress them out, what type of fish is it, it might stress out more intelligent species

 

Betta, mystery snails and shrimp

 

I doubt it. Unless you had a bird or cat trying to get in there, and even maybe not even then, they usually don't pay much attention to other animals outside of the tank.

 

My cat stresses out my ember tetras. They flee and hide as soon as she gets near the tank but it's probably because she sometimes jumps on their table and things shake a bit; that probably wouldn't happen with a rat. The fish in my other tanks don't seem to notice her even when she's pawing at the glass.