Small aggressive tropical fish

Aggressive Goldfish!

I've had my redcap oranda goldfish for a year now, and just recently (a couple of hours ago) added a calico telescope goldfish. The only issue is of the large gap in size, in which the oranda takes full advantage of, and continuously bullies the smaller fish. Is this normal behavior? Are they trying to create a pecking order, or should I be worried?

I haven't heard of this before, but the tank you have them in is way too small. A goldfish needs a bare minimum of 20 gallons, with 10 additional gallons for each additional fish. The fact that they're so cramped could play a pretty huge part.

I know the spacial situation is far from ideal at the moment, but I am currently cycling my new 40 gallon tank and cannot add the fish for another two weeks. I just separated the oranda to try and get it to calm down, and give the new goldfish a chance to familiarize with its new environment. Do you have any advice?

Welcome to FishLore!!
I've had this problem before with a comet bullying a fantail. It was awhile back, but I put the comet in a spare tank for (I think) 2 days. That solved it - after reintroducing him, he didn't bully the other fish.

Good Luck!

Welcome to the forum!

Goldfish are social and interact with each other pretty regularly. The 3 I have are all different sizes. There are 2 in the 90, and one is twice as big as the other. The third is new and in quarantine. It's maybe a third the size of the smaller of the 2. I honestly am not sure how it will be received.

How large are your goldfish? I just noticed that according to your aquarium info, they are in a 12 gallon tank. There's nothing I hate more than telling someone new to the site that their tank is too small......but your tank is way too small for 1 goldfish, let alone 2. The aggression could very easily have to do with the lack of space.

Thank you so much! After removing the larger goldfish yesterday for about 2 hours, I rearranged the tank a little. When I reintroduced him to the tank, all was fine. Both fish seem to be getting along for now, and hopefully their behavior will continue. Thanks again for helping!

Thank you so much! No worries, I know it's too small.. I got the new goldfish a little sooner than planned and am currently cycling a new 40 gallon tank, in which I will be transplanting the fish in about 2 weeks. The larger goldfish is about 2 inches and the smaller is about 1.3 inches including tails. I quarantined the larger one yesterday for 2 hours until it calmed down, and then readded it to the tank. The fish are now getting along, and are awaiting their brand new home! Thanks again, it's always cool to hear from a fish master, I'd be lost without this site!

when you switch them to the 40, I'd put the little guy in first and then add the more aggressive fish :-)

Good morning and Welcome to Fish Lore!

I have merged your two duplicate threads. Please only create 1 thread per topic. Multiple Threads on the same subject can be very confusing to other members.


Freshwater aquarium

by sage9x

A saltwater aquarium is going to be a massive time suck and a money pit. I advise against it. I really enjoyed my freshwater aquarium, but I never really had a problem with hard water. They make water conditioners for that, though.
I really enjoyed my freshwater aquarium. It was not that expensive, and if you get the right kind of fish, they are hard to kill. I stuck with Rafael catfish(hard to find the spotted kind), senegal bichirs(some people call them dinosaur eels), chichlids(super aggressive), and oscars. Don't forget to also include an algea eater(like a pleco), and several mystery snails

Adult Corydoras Catfish to a good home.

by Manticor892

I have a twenty five gallon tall planted aquarium and I bought a tiny little cory cat not realizing at the time that they grow to be ~3 inches long. I have plenty of room in my tank but honestly my cat has become too aggressive to other bottom feeders like algae eaters for me to keep him. The aggression is probably due to the size of my tank and my oversight. He has never been aggressive to mid or high water community fish. I am happy to give him away to someone who has a good size freshwater aquarium. I can provide a picture if necessary but a quick Google of corydoras will give you a good idea

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