It's brown, looks like a piece if his food. It's hard to get a picture because where it is.
What size is your tank? 3.5
What temperature is your tank? 30 C
Does your tank have a filter? Yes
Does your tank have an air stone or other type of aeration? Nope
Is your tank heated? Yes
What tank mates does your betta fish live with? None
What type of food do you feed your betta fish?
How often do you feed your betta fish?
How often do you perform a water change? 1
What percentage of the water do you change when you perform a water change? 74%
What type of additives do you add to the water when you perform a water change? Aquafin Chlorinator
Have you tested your water? If so, what are the following parameters?
Symptoms and Treatment
How has your betta fish's appearance changed? N
How has your betta fish's behavior changed?
When did you start noticing the symptoms?
Have you started treating your fish? If so, how?
Does your fish have any history of being ill?
How old is your fish (approximately)?