What fish can be kept in a demijohn?

[Kezae]

Hello,
My mum wants to get my nephew a goldfish, keep it in a demijohn.
They asked me, I said no they can’t have a goldfish in a demijohn.

What are your thoughts on this? Could you recommend another fish specie that could be kept in a demijohn?

Thank you

 

[Hufsa]

Absolutely no fish species can be kept like that.
Among numerous reasons the gas exchange surface of the water will be far too small. I dont even think shrimp would like it in there.
There are a variety small snails that might do ok if the container is well planted.
But please, no fish, it would be so cruel

 

[LightingBamboozled]

If you mean a normal size 1 gallon/5 litre demijohn then I agree with the above. You can get 55Litre "Demijohns" which if filled with about 45L of water would have sufficient surface and volume to support life. It would be a bit of a bugger to maintain though. Tools through the narrow neck etc.

 

[John q]

What are your thoughts on this?

I'd whole heartedly agree with hufsa, a 5ltr bottle isn't sufficient to support the life of any fish, yet alone a goldfish. I'd even suggest having snails in said bottle would be impractical, simply because of the difficulty you'd have trimming the plants and cleaning the internal glass.

Hey, at least you asked, so that's something.
My advice for the demijohn, turn it into a terrarium, be fun to plant, but won't require much maintenance 😉

 

[hypnogogia]

Hello,
My mum wants to get my nephew a goldfish, keep it in a demijohn.
They asked me, I said no they can’t have a goldfish in a demijohn.

What are your thoughts on this? Could you recommend another fish specie that could be kept in a demijohn?

Thank you

Absolutely nothing. With the thin neck it’s the wrong shape to allow for adequate gas exchange at the water surface. Also, there’s no way to float Fish in a bag in it to acclimatise, let aline easy access for maintenance or, dare I say, removal of dead fish. It’s really not an good idea.

 

[hypnogogia]

My advice for the demijohn

Make some booze!

 

[Tim Harrison]

That would be taking fish keeping to a whole new level of cruelty. As mentioned above it’d also be unsuitable for keeping shrimp. Not just in terms of volume but also access. Why not just plant it up as a bottle garden?

Bottle garden

Thought you guys might find this interesting... http://www.dailymail.co.uk/sciencetech/article-2267504/The-sealed-bottle-garden-thriving-40-years-fresh-air-water.html

www.ukaps.org

 

[castle]

If you have plenty of fish keeping experience, then I wouldn't blanket say that volume cant support "cool" life, while I don't think fish would work so well, I've kept shrimp and snails in about the same volume and they've been long lasting. The important thing is with such small volumes is making sure temperature stays consistent, and airline tube in would help a bit. By not filling it up to the top, you'll increase surface area. Small volume tanks are probably the most demanding of all freshwater tanks, so again, not right for a novice.

As I assume the nephew has little fish keeping experience, and is of a young age; for your nephew, and the fish; steer your mother towards Sea Monkeys.