curing Ick in a cold water tank

Hello all.

To keep it short, I have a cold water goldfish/Koi tank with Ick, LFS told me to use coppersafe and I did, read forums saying that that was bad and am asking if Coppersafe works, and better, if there is anything else I can do. I am very scared of losing my fish... please help...

Video of my fish with spots. sorry its inverted. stupid phone...


Full Story below:


I am not an expert fish person. I have had fish for 5 years now, started with 2 golds in a 10 gallon moved them to a 20,added some fish then 45, then a 75 added some fish, and now I just moved them all to a 125 last week.

I have 6- 4" SplitTail golds, 1 - 13" long tail comet thing, 4 - 4" butterfly koi, 1- 16" Sailfin giblicep Pleco, 1- 8" normal Pleco, 1- Pimodella cat, 3- Otto Cats


I noticed that the two newest Koi have white spots and found out that it's Ick.
The Ick is only on two fish but from what i have read, the whole tank is screwed...

I have read around 30 different posts from all around the internet.
It keeps saying turn up your heat but they are cold water and I don't own a heater :/ also I was told by my LFS to use coppersafe, the bottle said it treated 94 gallons so I put the whole bottle in. Of course after the fact I find some posts saying that that is really bad for fish?

Any advice/direction would be really appreciated. I would be really sad if i lost some of my oldest friends with fins.

PH 7.6
ammonia 0 ppm
Filtration - FX5 642 gph
I attached a picture of my tank as well

Please let me know if you need more information!