Rocks and stuff in pump basket at startup

[Timujin]

Pool was started yesterday. I do not recall seeing rocks in the pump basket because I looked inside of it to see if there were bubbles. Today I see some rock and other debris inside of the pump filter basket.
Is this normal?

 

[JJ_Tex]

Yes, you will see that with the startup of a pebble pool. Wait until you run your cleaner for the first time.

 

[YippeeSkippy]

Building debris.