The only way is to remove the top cover and push it out from the inside, to remove the cover you squeeze in the 4 tabs.According to the manual the pump is even more silent when not using the guard. @bubblemytip is that how you have yours set up?
I just ordered a second stream 3 so now I have two.
What is the best way to get the screen off the top. I find it difficult @rvitko