I've been keeping an eye on my beta and I just noticed a white spot on his dorsal fin - I'm pretty sure it's some kind of fungus, but I'm not entirely sure what's going on. He's been in his 10-gallon tank for a year now, and it's always been heated with a sponge filter. Recently I added some live plants I bought online, so I'm thinking maybe something unwanted hitched a ride into the tank. I did a water test with the API Freshwater Master Kit and here are the results:
Ph: 8.2
Ammonia: 0ppm
Nitrite: 0ppm
Nitrate: It's hard to read, but it's somewhere between 20-40ppm
Is my betta suffering from a fungal infection?
Re: Is my betta suffering from a fungal infection?
I took a closer look at your pictures, and the spot on your beta's dorsal fin appears smooth in the images. I'd like to know, though, does it seem fluffy or is it smooth to the touch?
It does resemble a cyst, which would be unusual, and there's some sort of buildup behind the lump, closer to the end of the fin. That might be normal, but if not, it could be related to the lump.
If the spot is fluffy, I'd say it's likely fungus.
If it's a cyst, you could try lancing it. To do this, carefully remove the fish from the water and use a sterile needle to puncture the cyst on a wet towel, so the fluid doesn't drip back into the tank. Then apply a drop of broad-spectrum medication to the site.
For direct application on a wound, Methylene Blue is a good choice. Apply one drop to the wound, wait 20 seconds, and then return the fish to the tank.
You could also try applying Methylene Blue to the site for a few days first and see if that improves the situation before lancing the cyst.
It does resemble a cyst, which would be unusual, and there's some sort of buildup behind the lump, closer to the end of the fin. That might be normal, but if not, it could be related to the lump.
If the spot is fluffy, I'd say it's likely fungus.
If it's a cyst, you could try lancing it. To do this, carefully remove the fish from the water and use a sterile needle to puncture the cyst on a wet towel, so the fluid doesn't drip back into the tank. Then apply a drop of broad-spectrum medication to the site.
For direct application on a wound, Methylene Blue is a good choice. Apply one drop to the wound, wait 20 seconds, and then return the fish to the tank.
You could also try applying Methylene Blue to the site for a few days first and see if that improves the situation before lancing the cyst.
Re: Is my betta suffering from a fungal infection?
It's definitely smooth, and I can see why you'd think cyst, but to me it looks like a corydora egg - just a small, smooth white spot.
Re: Is my betta suffering from a fungal infection?
If it's smooth like that, I'd say it's probably a cyst or blister. Adding a drop of medication to the area a couple times a day for a few days might do the trick. If that doesn't help, I'd carefully use a sterile needle to see what's going on. If fluid comes out, it's a cyst. If it's hard, it could be something else like a calcium deposit or even a tumour.