How do you keep a cold water tank cold?

Goldfish are just fine at room temperature, and can survive up to about 30C for a while.

If you are comfortable in the room, so are they.

My old goldfish is in a pond that varies between 4C and 28C with the seasons, and may change by 10C in a day. It's been there for 9 years now.

Most goldfish die of polluted water in tanks that are too small, not because the temp is wrong. Big tank, lots of water changes, dont worry about the temperature.

Ian

Goldfish thrive when kept in aquariums maintained at a constant temperature between 55 and 72F. I think its proper to assume that, unless you're keeping your goldfish tank out on a beach in the middle of Hawaii, that your "room temperature" temperature will be around there.

In other words - normal room temperature is fine. You don't need a heater, you don't need a fan, and you definitely don't need to be dropping ice into the tank as that will stress the fish out because it will tamper with the temperature too much, causing a sudden fluctuation.

Room temperature is just fine for gold fish. I had an Oranda goldfish live in a room temperature tank for years. Goldfish in general are quire resilient fish and can live in a wide range of conditions. Although they are known to live in cold water tanks, there has been some debate that they can even live in tropical warmer waters (although not recommended). So in other words, your goldfish will be okay in a tank that has water temperatures that are dependent upon the temperature of your house, whether cold or warm.

Room temperature is fine for a cold water tank

Temperatures in the 70s are just fine for goldfish

dont use a bowl which will kill them its thank you to small for any fish. i'd recomand a 5 gallon lay gravel on the floor and mabey a log or some situation that they are in a position to circulate interior. they have kits that comprise a filter out and tank besides as a food pattern and faucet water air purifier. sturdy success

keeep it outside or put a fan by it? or put ice cubes in it??