What's happening to my Pleco (and others)?!

[Herefishyfish]

Hello,

I have a pleco and recently introduced some platys and a African frog to my tank. I introduced everyone slowly etc.

My pleco has been with us for 2 years now but he is VERY quickly deteriorating. My best guess is fin rot but it seems to be a very severe case. He was fine up until I added the other fish (all of which died within hours and the frog a couple days later).

Water perimeters were perfect, I checked myself for 3 days before adding new fish and had 2 different stores check as well, because we had just moved and had new water service. My water levels are still checking in as perfect, no issues, temp is 78 degrees.

Please see below photos. I know at this point he is probably not going to make it, but these are one day apart. Any ideas what is happening/happened to my 'perfectly healthy a week ago' pleco?!

 

[Leeatl]

I don't know what's happening to him , but I would say euthanize the poor thing , it has to be in agony and very doubtful to recover .

 

[libertybelle]

Also I’d double check the tank for levels as well as other things that could be causing water quality issues. Everything dying within hours of being added to your tank is definitely not a good sign. Could be they weren’t healthy to begin with or acclimation issues but I’d triple check everything to be sure.

 

[KatyLLL]

get another water testing kit? perfect parameters
should not end in death.