Do you keep your tanks cold or warm. I have one with no heater at all & in my big tank I am running a heater but I am wondering the very best temp to keep goldies at. I am thinking maybe a little warmer is better. What do you all think?

No, colder is usually better. Don't worry about a heater for them, room temp is just fine.

I guess it depends on your climate.

I'm in Chicago, and the weather here fluctuates like a crazy-man. Plus I have a smaller tank; smaller size = wider temp fluctuations.

I used to not have a heater...and my tank had a low of 68 and would go up to 70 by mid-day (during the winter here). However, since I have been dealing w/some sickness, I purchased a heater and have the tank at a toasty 73. And he is loving it.


Goldfish can tolerate cooler water temps. I know my guys were okay w/it being 68. I just now prefer it to be a bit warmer for him.

I would go w/ no heater.

As long as your tank doesn't go into the low 60s your good.

My big tank (with heater) stays around 70.....I think it's a tab cooler at the far end but not much. I know it is slightly cool to the touch but comfortable when I am in there redecorating or cleaning or whatever. The 29 does not have a heater & stays around 60ish....which is cool to the touch & more uncomfortable when cleaning. Both sets of fish seem to be doing fine!!

I think fish can do well in 70s, has your other tank always been that cold? If it has, and your fish seem fine, maybe itd be okay to leave it, and make sure it doesnt get any lower, and maybe a heater in case.

I tend to keep mine in the mid 70's. I have found that the fish seem to be alot more active,and that the warmer temps definately keep my" floater's",floating alot less. Without a heater,my tank temps fluctuated too much-even in summer,so it was all about stability for me when I started.