How to prolong your betta's fins

I have found that Pete's fins have been slowly worn away, from swimming along the glass of his tank repeatedly, Pete was trying to get at his food dish that I keep in front of his tank. After the container was covered with some paper, he almost instantly swam to the middle of his tank. hopefully, this should stop his fin wear and help him grow them longer.

Poor Pete

Poor Pete caught ick, it might have been the water, it might have been some leftover food, who knows. anyhow, I just removed him, put in 8 drops of quICK and put him back in again. The next morning, I walk into the the living room to find a very happy, and hungry Pete looking eager for his breakfast (thank goodness)