Cardinal With Finrot

[chesterjohn]

I bought a few Cardinals to up my shoal on Sunday, and they looked a bit skinny when I put them in, but all swam about happily and ate food. I noticed one had a fairly large white patch yesterday, and he was dead shortly after I noticed him. I then noticed another had a damaged tail, and when I woke up this morning, he was dead and the tail was completely gone.

I assume he had finrot and possibly some other parasite/disease, but my question is that all the other fish look ok atm, is it worth treating the tank incase, or is this bad and I should wait to see if any other fish take a turn before treating?

 

[Embrace]

With fin rot (if that is what it is), the best thing to do is 10% water changes a day. This will prevent further infection and it will heal the affected area within 5 days.