I know I'm late to the thread, but here's a little about my old friend "Holey" (about 24" when we lost him in '04 (RIP)
We got holey in late 2000 as a 'lil one, Not knowing what we were getting into. One morning when he was about 4-5", I got up to go to work and noticed something wrong...He had worked his way into a hole in one of the little statues in the tank and had been wriggling there trying to get out all night. He had a "Chunk" missing from his gut about 1/4" to 1/2" deep. I spent better than an hour trying before I was able to get him out and thought there was no way he would survive...But he was a tough one, and pulled through. Luckily, the hole was behind the anus but in front of the fin. It was an interesting day, showing up at the office, an hour late and drenched because of a "Fish Emergency"...(My boss didn't like this excuse)
He grew and grew, he was a member of the family and the reason our tanks grew, from 10 Gal to 55, then 75, and finally 180. ( I'm trying to find some good pictures of him because as he grew, it never regrew in that spot and was always a point of conversation when people notices his..."Dent".
Here's the best close-up I can find for now...Notice the hole under the third black spot...
Rest in peace '

' 'ol buddy...