Why did one of my angelfish puke?

My angelfish are very spoiled and picky eaters. They will not eat flakes or pellets no matter how hard I've tried. I even went without feeding them for a couple days thinking they would be hungry enough to eat flakes but they wouldn't. They will only eat bloodworms and mosquito larva. I've never heard of a fish puking but it might have eaten something when you weren't looking then spit it back out. That's what mine do if they eat a flake or pellet, they spit it right back out. I think it should be fine, just try different foods. My bigger angel will eat small cichlid pellets but that's it, they are all different and like different diets.

Feed them crushed fish food, they will eat fine...

you need to give it some air. preform the Heimlich maneuver