Skip header
Free Shipping Over $49

As an essential business, we are open and shipping as usual!

My ProfileMy OrdersMy AutoShipMy RxMy PetsMy VetsMy RewardsSign In

Fish Flex (cephalexin)

4.88 out of 5 stars
This Item Ships FREE!

Please confirm

This item is already on your autoship schedule! Are you sure you want to add it again?

Product Overview

How To Use

What’s in it?


Questions & Answers

Product Description

Fish Flex is a comprehensive antibiotic that uses cephalexin to treat a large variety of bacterial infections in fish. It is useful in treating many diseases associated with pathogenic bacteria. *Caution : Not for Human Use.  

Who is Fish Flex (cephalexin) for?

For use in ornamental and aquarium fish.

Why use Fish Flex (cephalexin)?

Fish Flex offers cephalexin monohydrate in a water-soluble formula for broad-spectrum protection against a large variety of bacterial infections of non-specific origin.

How does Fish Flex (cephalexin) work?

Fish Flex treats many non-specific bacterial infections in the most multiplying and active infection stages using cephalexin, a powerful antibiotic.


Thomas Laboratories

Active ingredient(s):


How is Fish Flex (cephalexin) sold?

30 or 100 capsules in 250 mg or 500 mg strengths

What special precautions are there?

  • Keep away from children.
  • Never use in fish intended for food use. Only use in ornamental organisms and fish.
  • Only for use in aquariums.

What to do if overdose?

Contact your closest emergency animal hospital.

How can I store Fish Flex (cephalexin)?

Store at room temperature between 59°-86°F. (15°-30°C).


Add contents of one capsule (250 mg) into aquarium for each 10 gallons of water to be treated. Repeat in 24 hours. It is suggested that a partial water change be made between treatments. While treatment duration depends on type and severity of the infection, it is recommended that extended medication baths continue for a minimum of 5 days and not more than 10 days. Discontinue treatment with this medication if no improvement is noted within 5 days.

Main Ingredients


Write a Review

Fish Flex (cephalexin)

Can you answer these questions?

Dog with UTI

0 Answer
Ask a New Question

Don’t know something or can’t find the information you are looking for? Ask us a question!

*Required Fields
We will ONLY use your email to notify you in regards to your submission.Privacy StatementQuestions & answers are typically posted within 24 hours, pending approval.