[Tiara Open] Round crack in gel coat on hull side

[Crown Royal]

            Pull my 2001 3500 open for new bottom paint and noticed a small circular crack about the size of a quarter it’s about fall way between the forward porthole and the boot stripe. I have had the boat 13 years and no other issues, was wondering if this could’ve been an imperfection when it was built ? Has anyone ever seen this before?
How about the proper way to repair. I will try to attach a picture.

[Sans Peur]

It's called a blister. They are usually below the waterline but I have seen them above. Get a good glass guy to fix it. Easy to do and shouldn't cost more than a couple hundred dollars. I just had 2 fixed on my boat while it was out of the water a few weeks ago.

[Crown Royal]

Thanks ! Always heard of them first one I’ve seen.