Okay, yeah I suspected double tail since they are notorious for having swim bladder issues or issues of any sort really. Double tail is actually a deformity in and of itself which then causes other issues, usually related to the spine. They tend to have bent and/or deformed spines which in turn cause other issues like organs being pressed together. One of my DT boy's has squished intestines so I'm lucky if he poops once a week but he still get's about 4 or so pellets daily of NLS with two fasting day's along with the rest of my fish since I'm not home.
And Aqueon is a bad brand to feed constipated/deformed fish. Since it has so many filler's it's a bad brand of food, it's like eating garbage and expecting to get nutrients from it :-/ So yeah, Omega one is the way to go ^_^ to know if it's a good brand you want to look at the first three ingredients, and this goes for all foods as well; human, cat, dog, rabbit, etc. And things like Wheat, Corn and Soybean are fillers which you want to stay away from. So you want to look for a food with little to no fillers in the first three ingredients
which Omega has no fillers in the first three, NLS has one but they make up for it by adding garlic and spirulina to their food!
and you're welcome, happy to help!