My beautiful calico oranda had been floating upside down for awhile. I tried different flake and pellet foods and this continued and worsened with every feeding. I started feeding frozen food exclusively and now he is totally fine. Anytime I feed flake (even good quality like Omega One), he floats upside down. So I'm wondering if anyone feeds frozen exclusively? I feed a variety pack that has fortified mixture of proteins and vegetables. They seem to being doing ok with this but I'm not sure how this will go long-term. I can feed fresh veggies too but I guess flakes and pellets are not options any more. Guess this fish has to be gluten-free.