Freshwater Aquarium/query


Hello,I have 3 goldfish and two bala sharks in my aquarium tank. My query is how do these fish live in the open wild without air pump. I am thinking of leaving them back to their natural habitat but they need pump in an aquarium , how do they survive in open waters. thanks

Hi Kelly!

Bala sharks are found in midwater depths in large and medium-sized rivers and lakes. They feed on phytoplankton, but mostly on small crustaceans, rotifers, and insects and their larvae. As for oxygen, natural bodies of water often have moving currents which supplies organisms with the oxygen they need. A waterfall for example, would cause air to crash into the water along with the water itself. In calmer waters, aquatic plants and algae release oxygen, providing fish their abundant supply of oxygen.

Hope this helps!


Freshwater Aquarium

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I can answer questions about betta, goldfish, aquatic snails, freshwater crustaceans, freshwater bottom feeders, and tropical fish. I have little knowledge on freshwater frogs/tadpoles. No saltwater fish/cichlids questions please! I do *NOT* know how to make Decor for tanks/aquariums. I can also help you if your fish is stress/sick and setting up an aquarium/fish bowl/tank/etc. I can also help you with disease/injuries/parasites/etc. I can also help you with compatibility of tropical aquatic animals.


I have 30+ years of experience with tropical fishes & bettas. If you have a question (sending a picture will help) just ask and I will reply as soon as possible!

I went to Stanford University (Graduated). Has a Masters Degree

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