I have had my betta fish, Yoshi, for 13 months. He lives in a 22 litre tank on his own. He is a very healthy boy, eats well, betta bites and occasional fresh worms and I have never had any health issues. I have a carbon filter in his tank..no heater at present as water temp is about 28 degrees, his tank is always kept clean and I add aquarium salt at the recommended amount. On saturday I noticed a brown thing near yoshis eye and I have no idea what it is or what I can do to help him. He is also swollen on that side and his scales around the area are sticking out like a pine cone. Any ideas what this could be and how I can help my dear little boy. ?? in the first photo you can just see the lump and in the second photo it looks like something sticking out ?? he continues to eat well but today (monday ) he is a little quieter than normal .