3 day old fish has fin rot

[sia20]

i have just bought 2 guppys three days ago found one dead tonight and one looking very poorly looking closer they have fin rot quite bad how long would it take a fish to catch this surley not 3 days would the fish of had it before i got them? testing my water it all shows fine and all my other fish dont seem affected by it

 

[Polardbear]

It is frequently brought on by stress, and moving into a new home can be quite stressfull. Also the conditions of the tank it came from will play a big part in it. They are usually overcrowded and stressed out from being shipped to the LFS. If you can isolate the remaining guppy from the rest of your fish and treat it with some antibiotics.

 

[Inchworm]

Hi sia20

Polardbear is right about how they were likely to have caught it. It's not an uncommon thing at all.

Finrot is a bacterial infection and there are many different strains of them. Some will kill a seemingly healthy fish overnight, while others will move more slowly.

If you live in the US you can get antibiotics from your lfs. If you are in the UK, the best medications to get are either Waterlife’s Myxazin or Interpet’s Anti-Fungus and Finrot.

Good luck. I hope your fish gets well soon.