Will harlequin Raspboras eat shrimp?

Most likely. Adults RCS would probally survive, but it will be hard to keep babies.

I have 10 Harlequin Rasbora in a tank with Red Cherry Shrimp and I have never seen them hunt them. And their population is growing.
Although, this is a 40 gal. long and has lots of plant cover for the shrimp to hide in.
I wonder how they would do in a more confined area.

i used to think they wouldn't too much, because they never eat anything thats not floating in the top third of tank. but something is making my RCS population shrink, either my harleys or assasin snails.

I have 6 Harlequin Rasbora and 75 rcs in a 10g. From what I observed so far the rcs babies and adults are swimming around with no problem. The fish seem not to pay attention to the rcs. Plenty of plants and places to hide in the tank.

I've found that harlequin rasboras are the least shrimp aggressive fish. Just provide the shrimp with some nice caves and hiding spots.