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Freshwater Aquarium/Fresh Water Fish


My Fish Tank
My Fish Tank  
Hi Elizabeth,

I would really appreciate some help. I have a 20 gal. freshwater aquarium with 5 fish. The one big fish bullies the others and is probably too big for the aquarium. Can you please look at the attached picture and let me know what you think? Should I bring the big one back to a local aquarium and buy 1-2 other smaller fish? if so, what kind?
These five fish (I don't know what kinds they are - one big one, two that are the same, one black angel fish, and a  plecostomus have lived together for the last 3-5 years.)

Thank you,


You can either take the fish to a store, or try adding a lot of decor/plants to lessen the aggression. If the little ones have plenty of cover, it might help. Alternatively, if you choose to take the fish to the store and get more, I recommend getting a small school of fish such as a type of Tetra or Harlequin Rasboras. They are known to be rather peaceful fish, and stay small. They just need to be kept in groups of at least five. If you are not looking for that many fish, you could get a platy or two.

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Elizabeth Turbyfill


I am available to answer any questions regarding Betta fish and goldfish. I will be able to answer questions ranging from basic husbandry to health issues and more. I have a fair amount of knowledge regarding keeping freshwater fish in general as well, excluding cichlids. If you have any questions about species compatibility, maintenance, health issues, et cetera I can help. If there is a question that I do not know the answer to, I will look to reliable resources to find the answer.


I have kept numerous Betta fish and freshwater aquariums for several years, and have spent countless time researching them.

I am a member of a fish forum named Tropical Fish Keeping that I highly recommend to people who keep aquariums or just have complex questions that cannot be answered here.

I am currently attending East Tennessee State University for a bachelor's degree in Computer and Information Science.

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