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My betta fish is sick with fin rot and lethargic. How can I save him?

Updated On September 23rd, 2025

Pet's info: Fish | Betta | Male | unneutered

Hi; I have a betta I purchased about 3-4 months ago. He started to get fin rot, so i purchased Bettafix and did a 100% water change. However since yesterday (first day with bettafix) he is lethargic; all day today he was at the top (by the heater which keeps his tank at 78 F) but now hes at the bottom. Looking almost lifeless. Is there any way I can save him?

1 Answer

Most Helpful Answer

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Answered By Todd Cecil

Veterinarian

Published on February 26th, 2019

Thanks for reaching out about Flippy. A veterinary visit is highly recommended. Testing water quality for ph, ammonia, nitrites and nitrates, correcting any concerns. Water must be dechlorinated for several hours at least, prior to adding to the tank. Laying on the bottom could be a sign of a swim bladder infection and loss of buoyancy. Systemic antibiotics, not water additives, are recommended. Bettafix as a water additive does little for systemic infections. Good luck.

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