Tavel

I bought a pair of yellow rainbow fish (Boesemani) and my other fish attacked and killed one of them, and I segregated the other before they hurt him.
Why would my giant danios and congo tetras attack and kill a fish? They're normally very docile and playful with other fish. Is it because the rainbows were yellow?

Thankfully the fish store accepted the return, but even they were clueless as to why danios and congos would attack a fish.

I'm asking because I still want to get rainbows, maybe a different color, but I don't want those getting killed too.

Shawnie

im sorry your fishie was killed sometimes all fish take offence to newbies..

knowing this info about your nawty danios, maybe take them all out into a bucket, re-arrange the tanks deco, put in the new fish first...wait a bit then release the nawty kids back after ...goodluck!

Tavel

would I have to permanently re-arrange it, or could I revert to the old arrangement after a week or so. I really like my current setup, I could deal with a temporary setup but would ultimately want to go back.

jdhef

My guess is that you could probably revert back after a couple of weeks.

Tavel

I noticed some odd behavior from my fish, and your input about territorialness clicked. So I've decided to re-arrange the tank anyway. I think I like the new arrangement better, but maybe I just like the change. However, the fish are now moving about the entire tank again instead of being confined to their specific territories.

A big danio laid claim to the left half of the tank (half of a 75gallon, wow) and would chase any other fish away...except the barbs.