Wait found this, see how all his fins blend together to make almost a D shape out of them. He isn't fully flared here, this was from when I changed his tank and he freaked out the water was missing and flared at me when i brought the cup in to take more. Ignore the text xD
Another view still not fully flared but pretty relaxed. It's hard to catch him just when he is flaring, he moves so fast and falls out of it so quickly. I'll keep trying.
Edit got some half way decent flaring pics, adding now.