Help I Don’t Think They Have Long.

I currently have horrible parameters. Got diagnosed as old tank syndrome and I’m working on a massive water change and deep clean now. Just noticed this on my mollies this one in particular has the shimmies baddd. It’s got this on its mouth and little whit stringy things on him and a white fuz. What is it???? He’s gone isn’t he );
Edit:I’m sure most of you know but it’s a Dalmatian mollie so most of those white spots are natural

 

That looks like Columnaris to me. Yes he's a goner. Any fish showing similar symptoms should be removed from the tank asap. I have no knowledge concerning "Old tank syndrome".

 

That looks like Columnaris to me. Yes he's a goner. Any fish showing similar symptoms should be removed from the tank asap. I have no knowledge concerning "Old tank syndrome".

I have no quarantine tanks or anything so do I just euthanize him? Sad

 

That's your call, but its a pretty good bet the fish is suffering.

 

I did, it’s sad but better then suffering or spreading