Salt AND treatment for ick at same time?

Question
I have 4 goldfish and ick is covering 3 of them. the 3 original big ones.  The new tiny one is happy as a fish, the others are lethargic as death.  I am doing partial water changes and adding salt.  It is also adviseable to use jungle LifeGuard All in One treatment (i gave one dose) or should i use one or the other?  and which?  All water parameters are stable, tank set up 3 years ago, it appears to be ick from the new fish.

Thank you.

Also, what is your opinion on heating the tank?

Answer
Hello,
I am very sorry for my slow response.

By now you have probably made a decision, and with goldfish, all of the above would probably be fine.

I would use just the jungle lifeguard, as I personally do not like the addition of aquarium salt.

As for heating, don't bother. goldfish actually prefer water cooler than 65 degrees and warmer than 32 degrees. If you want a temperature controll device, I would actually recommend a chiller.