Is This Finrot?

ill get straight down to it i just found my female betta in the tank looking very sick. it looks like rapid on set of finrot. this morning she was fine and now tonight her dorsal fin is non existent as is most of the rest of her fins and it looks like her skin is peeling off. i have some pics but there is poor lighting over the hospital tank and the quality is bad. i have started treating her with science products fungus and finrot remedy.

the tank she was in;

Ammonia 0
Nitrites 0
Nitrates 20
pH 7.2

4ft - 260L

filters

aqua one cf500 canister filter (500lph)
aqua one 1200 power head (1200lph)
& a aqua one 102F (500lph)

i know its over filtered but the canister filter is only new so i have left the other filters in there. no one else in the tank is showing any signs of sickness but i added a few new fish today (before i saw her) so i decided to treat the tank with melafix. it says on the bottle that you can also use it when adding new fish to the aquarium so i figured it wouldnt hurt to treat it just in case. im guessing anything fungal would be contagious. anyway am i treating her right? the pics are green due to the finrot treatment

Get going on a bacterial med.
Peeling skin can be poor water quality, parasites to bacterial.
Anys signs of flicking and rubbing against objects.

Wilder said:

Get going on a bacterial med.
Peeling skin can be poor water quality, parasites to bacterial.
Anys signs of flicking and rubbing against objects.

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havent seen anyone flicking. i was thinking, could it be some back lash from my heater over cooking wy water the other day?

alas i got up this morning and she had passed. she had a huge hole in her side am glad i started treating the big tank with melafix last night. no one in there is showing any signs of anything but my water stats are fine so im assuming its something parasitic or bacterial as you said.

R.I.P.
It's bacterial then sorry.
http/www.nationalfishpharm.com/articles.html

Wilder said:

R.I.P.
It's bacterial then sorry.
http/www.nationalfishpharm.com/articles.html

Click to expand...

oh dear! that does sound nasty. fingers crossed it hasnt spread to the others in the tank...only just got a few new fish to replace the ones that died the other day

I would preform some water changes for a few days.
I wouldn't get any new fish for at least a month just to be on the safe side.
Good luck.

Wilder said:

I would preform some water changes for a few days.
I wouldn't get any new fish for at least a month just to be on the safe side.
Good luck.

Click to expand...

roger that! have just finished a 25% water change. everyone else is still looking ok but then again she looked fine a few hours before

thanks for your help
you seem to be the person to talk to regarding disease and stuff

Good luck.