Watery poop normal?

My baby has had watery poop for over a month. He goes once (sometimes twice) a day and his doctor isn’t concerned because he’s gaining weight. He’s 9 weeks old this week and two weeks ago when I took him to the dr because I was concerned that we should change his formula, he weighed 12 lbs 12 1/2 oz. His 2 month check up is this Friday and I’m sure he’s well over that weight now.

Does this look normal to you? He’s on Similac Pro Total Comfort and the dr doesn’t think we need to switch formulas. She said some babies just have watery poop. He’s not fussy and has 5-7 wet diapers a day.