I got my Betta today and I noticed that he has something by his gills or around that area (or at least it looks like he does) , and also, is his tail damaged (or is it fin rot or something else)?? If something is wrong could you please tell me how to help him. Here is a picture:
Some information you might need to help:
My tank is 21liters or 5.5 gallons, The tanks is newly set up, so about 3 weeks, I use a marina filter which could be used on up to 30 liter tanks. It is 22 celcius (i have a heater). I have fed him some bloodworms and betta pellets which he ate a bit of (not very much) but he did just arrive so I think he was a bit stressed from the trip here. He was the only male in a tank with many (about 15) female bettas in the petshop so that might explain why his tail is a bit damaged from them nipping it.
I use a test strip (Tetra 6in1 test) which says:
Ph = 6.8
GH (general hardness)= 12
KH (Carbonate)= 4
NO3 (Nitrate) = 10
NO2 (Nitrite) = 0
Cl2 (Chlorine)= 0
None of these things seem wrong to me, but correct me If I am wrong!! I just want my betta to be a healthy little guy!