Mystery Snail Growth??

So I bought this guy 6 days ago(Friday) and put him in my 38 gallow bowfront. He's with 8 albino cories and one lone ghost shrimp. I feed them algae wafers and shrimp pellets.
Is it possible he's grown that much in less than a week? What looks like a growth band was half that size on Monday.

 

38 gallon bowfront sounds like an endless supply of delicious biofilm lol
he's a real looker tho :]
once he makes his rounds he won't grow so large so quickly but in a couple months or so you'll have a golfball snail

 

Yea there's plenty of biofilm for sure. But he prefers the algae wafers. He comes from across the tank to steal bits from the cories. Lol
I just didn't think they grew that fast. It looks a little thin to me but I'm not sure on their growth rate.

 

More than possible, I was just going to ask the same, mine also has just sprouted off