Schooling fish that coexist with goldfish?

depends on what "medium sized" is. I would think white cloud mountain minnows would do well, as they like cooler temps like goldfish.
 
White clouds are about the only thing suitable temp wise, and those would get eaten as soon as the Goldies get any size on 'em at all. A yearling Koi will easily eat them.

And FWIW Goldfish regularly get smaller fish caught in their throat and choke- you need to be on standby with a pair of long tweezers if you plan on doing this.
Most experienced Goldfish keepers don't keep any other species at all with them.
 
Goldies all alone, plus koi

Yup, goldfish and koi, nothing else. You wouldn't see a tropical fish well from above anyhow.

No tropicals, no plecos (horrors), no catfish (impossible to pull out of the goldfish throat)
 
Drats.

Wasn't talking mixing in tropicals, already knew better than that at least. I've been keeping goldfish and around koi for the last 4-5 years and can't say that I've seen any hostility between them..

And this is why I ask months before I'd even pickup a tool.. So I have plenty of time to change my mind and replan! :D

By medium size, I was meaning something that would hit a 6-8" range.

I was (and still am) planning on a 300 something gallon tank. Just can't decide what will look good to populate it with. Probably staying cold water because.. its closest to what I have the most experience with.
 
Originally posted by aquariumfishguy
Erm... I wouldn't even keep Koi with Goldfish, not unless they were in a large pond. In an aquarium, the Koi could really harm a Goldfish.

Koi are goldfish.
 
koi are a recent subspieces of japanese and german carp. Some of the more recent strains exist from crossing with nearly-wild carp.

goldfish are a several thousand year old engineered fish. I'm not immedately able to locate what their original parent speices was.

However, most taxanomists would say that if two creatures cannot breed, then they are not the same speices. I am not aware of any koi/goldfish crossings so I would presume they are quite seperate.


Hmm. I am finding some references to zebra danio's maybe working.. but I'm worried that they maybe too small..
 
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