Has my Goldfish "frozen" to death?

[Augustjd27]

I picked up a fancy goldfish yesterday from Aquarium Coop and transferred him to my new outdoor, unheated aquarium. I figured 40 F wouldn't be ideal for him, but I was surprised to find him dead/immobile on the bottom of the tank this morning. He looks totally healthy but his operculum didn't appear to be moving so I believe he's a goner😔. Just in case he's still alive, I'm adding a small 50 watt heater to hopefully bump the temp up to 50 to see if he wakes up. 

I feel really stupid for not anticipating this happening and using a heater to begin with. Can fancy goldfish survive sub 40 temps? Was it just too sudden a change for him to tolerate? Chances he could still be alive?

Edited December 4, 2020 by Augustjd27
Punctuation

[FrozenFins]

no. There tempeture range is like high 50F to like 72F.

[JettsPapa]

I keep common goldfish outside in cattle troughs to control algae and mosquito larvae, and while it isn't common in my part of the world, it occasionally gets cold enough for a layer of ice to form on top, and the goldfish survive it just fine.  With that bring said, I suspect the temperature change your fish went through was just too abrupt.

[lefty o]

the abrupt change may have done it, but worth trying to warm it up. i remember in high school science class freezing gold fish in liquid nitrogen, and thawing them out, and they survived just fine. dont give up hope.

[FriendlyLoach]

Regular goldfish are good with cold, fancy ones are not. However I think it was the shock that did it. I think he is dead. 

[Streetwise]

I have kept shrimp and White Clouds in outdoor tubs that were good in a wide range of temperatures. However, I would recommend slow temperature acclimation, even for the most hardy species.

Here in Vermont, I have to move everything indoors for the off-season.

Edited December 5, 2020 by Streetwise
Temperature

[David Ellsworth]

I agree, rapid temp change is likely the culprit if the tank parameters are all up to snuff. Fish would need time to prep for winter temps. Fancy are more delicate than comets and koi, but it also depends on the pond depth, insulation, and your average winter temps. 

 

Koi or gold fish ponds that over-winter here in the midwest (we get really cold here like -40 F or more at times in South Dakota) you want something 6 foot deep or more. That gives better water stability temp wise and the top can ice over at the top and have a separate warmer water zone at the bottom of the pond.  So you get temperature layers. You really can't do that with the pond tubbing with totes that is popular with many of the youtubers in really colder temps.

 

Lucas from LRB Aquatics had some whiteclouds in Indiana (I think) with a thin ice layer over the top and they were fine, but he has his tubs in wood enclosures that are covered and insulated too. His guppy ponds are heated with a 500watt heater and covered. 

 

I don't know about the different goldfish, but I do know that koi don't feed below a certain temperature so you need to build up their body fat and keep them healthy the rest of the year so that they can go into low maintenance mode. So there is body metabolism based on species.   

[Augustjd27]

Unfortunately the fish passed away. I left him with heater raising the temp overnight and smell clearly indicated this morning 😔. I don't care at all about the investment lost, just feel really bad for killing that fish. Definitely going to prepare better next time. Thanks everyone for the advice.