So about a month ago one (out of two) of my Oranda goldfish started to struggle to swim straight and would often turn sideways and occasionally swim upside down. Immediately I reduced the amount of food I was giving them and the following day did a water change beforetreating with interpret swim bladder, as this is what I believed it was. After the 12 day course I did another water change (30%) but the fish had not seemed to get any better. For the next 7 days I also tried changing food source to sinking pellets but no luck. This is the third time in about 3 months it has gotten sick, the first time it got popeye which I treated with interpet anti-bacterial medicine and aquarium salt which worked, the second time it developed a white cotton type growth on its abdomen coming through from under its scales which I treated with interpet antifungus and finrot meds,which also seemed to work. Now for the past 24 hours it has predominantly just lay at the bottom of the tank not even trying to swim and showing no interest in food. Since it has been over 7 days since I used swim bladder treatment I have done another water change and tried the antibacterial and salt treatment again. Does anyone have any idea what could be the issue and what else would possibly fix my fish? The other oranda who has been with it from day 1 (about 1 year ago) is fine and has never had any issues. His body is much slimmer than the one which keeps seemingly having problems. The ill fish has a round abdomen but is much bigger and has a larger tail. If I'm being honest out of the two it appeared the more healthier fish to look at. For information I have a 60L tank with 2 large filters and plenty of oxygenation. I perform water checks at least weekly and it has been a good 6 months since I've had results even slightly off optimum. They used to be fed mainly flakes but I've recently started to incorporate pellets and frozen Bloodworms. Water changes are accompanied by adding API products for tape safety and biological enhancement. My filter also has cartridges Ciano water clear and Ciano bio bact. I also have two Nerite snails which have never caused any issues as well as Anubias and java fern plants which have never caused any issues. Tomorrow I am going to try them with peas as I've heard this is good for fish health (if he wants to eat that is) Update* Tried with peas and it ignored them. Has developed white stringy growths on abdomen. Have treated with interpet antifungus and finrot med and added more Epsom salt Any help would be appreciated.