Rinsing Gravel

Yes, you are fine.
 
What I used to was take a strainer like the type used for noodles and put a piece of mesh in that to keep the gravel from going through it and put a load of gravel in it. Then I'd put that under a shower running the hottest water I could get out of it for a bout 5 or 10 minutes, then run cool water thought it after that.
 
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