Question
There are white patch/spot-like marks on my betta fish's gill and body, which were not there when I bought him from the store.
He is his usual active self and is eating properly. The spots seemed to have appeared after I have done water change. I use Seachem water conditioner to treat tap water that I use for the aquarium. The only decoration in his tank is an artificial plant and a tree log for hiding.
I have attached the photos. I am not sure whether he is ill or injured from decorations?
Answer
While the photo isn't conclusive the most common cause for "white spots" on a Betta is Ich, it's exceptionally common in Betta, and if left untreated can be fatal. Fortunately however it's relatively straightforward to treat.
From the link:
Move the betta to a hospital tank if there are other tank mates.
Increase the temperature slowly in your tank to 81-86 degrees fahrenheit for up to 10 days. Ich parasites prefer colder water, with colder temperatures leading to prolonged life cycles and increased reproduction rates.
Warmer water holds less oxygen, so consider adding an airstone. Increased oxygen can boost a betta fish’s immune system.
Follow the directions and administer the recommended medicine for treating Ich: (Rid Ich Plus) which contains malachite green and formalin. It is strong and highly effective.
Perform daily water cycling of 25-50% to reduce high medication levels and remove Ich trophonts and tomites.
Continue medication according to the directions and do not stop early. Ich protozoan are only vulnerable to medication two days out of their seven day life span, so continue even if they appear to be gone.
Answered By - motosubatsu