# Goldfish died, after adding new one



## Seena (Aug 21, 2012)

I just started my 20g aquarium, did a fishless cycle until nitrats appeared. And now I have 0 Ammonia, 0 Nitrites and probably 5 ppm nitrates, after a big water change.

I added first one small fantail fish, which did very well. Was very active, swam thoughout the whole tank and after 2 days even learned to come to the surface when I was opening the lid to feed. Really, everything went well.

After 3 days I bought another fantail, similar size, same shop and basically same tank there. After adding the new one, the two were always swimming around one another, seldomly more than 1 inch away. Sometime it was like in parallel and one moved a little, then the other one moved a little. A few times I saw the new one trying to nip on the fins of the old one.
In summary the behaviour of the old one now totally changed. It was very quite, not really active and finally went to hide somewhere in the tank, whereas the new one was cruising around.

This morning I tried to feed them. The old one came to the top, but swam right through the food and didn't touch it. Just yesterday when it was alone, it would have eaten everything. Finally, it went to the bottom of the tank and stopped moving. After a while I got worried, went down with the net just to check whether its alive, but it was not moving any more.
The new one seems to be fine. It swims around in the tank, ate some food.


*frown*frown*frown Any ideas what happend?


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## fishenthusiast123 (Aug 22, 2012)

two things i can imagine what happened. even though two fish are exact species and alike, territories progress especially if the second fish when in the tank after the first. the first established dominance hence the reason he/she was swimming around the tank and the discovery of the other fish is a way of figuring what it is and how territorial it can be. The only other possibility i have is there was a heavy ammonia level the fish released into the tank due to being chased and made the other one sick....


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## navigator black (Jan 3, 2012)

Ammonia burns are very specific.
I would say it could have been a same sex pairing - two males. I've never seen goldfish fight though, but then again, I have only kept a few.
The other, very likely cause was random bad luck. One just died and the cause will never be known.


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## fishenthusiast123 (Aug 22, 2012)

The only other thing i would suggest is a parasite but if it wasnt swimming funny not sure. Goldfish are notorious for not showing signs till its too late


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## Seena (Aug 21, 2012)

Thanks guys. I mean they didn't really fight, at least what I saw. No idea what happened during the night, but in the morning I couldn't see any signs. Somehow the first fish, got kinda into a "depression" when the other one came in and then was dead after less than 12h.

I really hope there is nothing wrong with the tank. Yesterday ammonia and stuff looked great...will check later again.


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