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I have a 20 gallon tank. I'm thinking of buying +5 fish. Which fish could I buy and what would I need for the fish and tank?
2 Answers

Answered By Angel Alvarado, LVT
Licensed Veterinary Technician
Published on November 23rd, 2017
Answered By Angel Alvarado, LVT
Licensed Veterinary Technician
Published on September 11th, 2017
At the very least, a 10 gallon tank with a filter, heater, hood and light. Ideally, the tank should be up and running (without fish) until it cycles properly. This means there needs to be sufficient time for beneficial bacteria to colonize the tank and filter to be able to break down wastes, namely ammonia and nitrites and to a lesser degree, nitrates. This can take several weeks to occur.
You can cycle a tank with fish in it, but it will require daily testing of water chemistry to prevent a toxic build up of ammonia and/or nitrites. Either can kill your fish if not treated.
Follow this link for a FAQ regarding Glo Fish: https://www.glofish.com/about/faq/
Follow this link for more about cycling a tank: http://www.firsttankguide.net/cycle.php
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