Fix Pen (Penicillin) Tablets Fish Antibiotics - 500-mg (30-count) - Fish Medication and Vitamins 1
Fix Pen (Penicillin) Tablets Fish Antibiotics - 500-mg (60-count) - Fish Medication and Vitamins 2

Fix Pen (Penicillin) Tablets Fish Antibiotics

★★★★☆ (22 reviews)
Regular price$41.99
/

Size
  • Made In USA
  • In stock, ready to ship
  • Inventory on the way

Eliminate Harmful Bacteria Quickly in Aquariums

Product Description

Fix Pen 500 (Penicillin) Fish Medication is a powerful antibiotic designed to protect your fish from bacterial infections. This medicine works on the main types of bacteria that make fish sick, like flexibacter, fin rot, and tail rot. It keeps your fish healthy, helps them recover faster, and comes from the USA with no fillers or extras.

Important Notice:

This product is intended for fish use only. It is not for human consumption. We do not sell or recommend this product for human use.

Benefits

  • Effective Infection Control: Rapidly combats common bacterial infections in fish, ensuring healthier aquatic environments and preventing disease spread.
  • Targeted Bacteria Elimination: Specifically treats gram-positive and some gram-negative bacteria affecting fish, maintaining tank balance.
  • Protects Fish Health: Helps recover from flexibacter, fin rot, and tail rot infections efficiently.
  • Safe and Pure Formula: Contains no fillers or additives, ensuring only the active medication affects fish health.
  • Trusted Quality: Manufactured in the USA with strict standards, delivering a dependable antibiotic solution.

Variants

Available in two sizes:

  • 30 count
  • 60 count

Ingredients

Active Ingredient

Active Ingredient (per tablet)

Amount

Penicillin

500 mg

How to Use

Directions for Use 

  • Dosage: Add one 500mg tablet for every 20 gallons of aquarium water to treat bacteria effectively.
  • Repeat Treatment: Repeat the same dosage 24 hours later to make sure bacteria are fully controlled.
  • Water Change: Do a partial water change between treatments to keep the water clean and safe for fish.
  • Treatment Duration: Continue treatment for at least five days, but no longer than ten days, depending on infection severity.
  • Monitor Improvement: Watch your fish carefully; if there’s no improvement after five days, stop treatment to avoid overmedicating.

Additional Information

Precautions

  • Proper Storage: Keep the container tightly closed, storing in a cool, dry place away from moisture.
  • Not for Human Consumption: Do not give this medication to fish intended for human consumption under any circumstances.
  • Overdose Warning: In case of accidental overdose, immediately contact a qualified health professional for proper guidance.

Shipping & Return

We offer ground, express, priority, and international delivery; see our shipping policy for details.

For return instructions or product concerns, please refer to our detailed refund policy.

Frequently Asked Questions

Q1: How does Fix Pen 500 (Penicillin) fish medication help treat bacterial infections in aquariums?

Ans: Fix Pen 500 (Penicillin) fish antibiotic targets gram-positive and some gram-negative bacteria. This medication helps prevent common diseases like flexibacter infections, fin rot, and tail rot. Its pure formula contains no fillers and is safe for all aquarium species.

Q2: Can I use Fix Pen 500 (Penicillin) tablets for all types of fish in my tank?

Ans: Fix Pen 500 tablets are perfect for keeping your freshwater fish healthy. They fight harmful bacteria and help your fish bounce back from fin rot, tail rot, and flexibacter infections when used properly.

Q3: What is the correct way to dose Fix Pen 500 (Penicillin) for aquarium treatment?

Ans: Add one 500mg tablet of Fix Pen 500 per 20 gallons of aquarium water. Repeat the dose after 24 hours. Make partial water changes between treatments. Duration depends on infection severity, but continue at least five days, up to ten.

Q4: How long should I continue Fix Pen 500 (Penicillin) treatment for my sick fish?

Ans: Fix Pen 500 treatment should continue for a minimum of five days, depending on infection. Do not exceed ten days of use. Monitor your fish daily while using Fix Pen 500. Discontinue treatment if no improvement is observed after five days to prevent unnecessary exposure.

Q5: Is Fix Pen 500 (Penicillin) safe for use in aquariums with edible fish?

Ans: Fix Pen 500 (Penicillin) is strictly for aquarium fish, not for human consumption. Do not give it to fish intended for eating. Use Fix Pen 500 only in ornamental aquariums.

4.5
Based on 22
Reviews
★★★★★
17
★★★★☆
4
★★★☆☆
1
★★☆☆☆
0
★☆☆☆☆
0
John D.
★★★★★

Fast delivery and the Fix Mox was exactly as described.

June 18, 2026
Sarah M.
★★★★★

Good packaging, Fix Doxy arrived sealed and in great condition.

June 15, 2026
Michael R.
★★★★★

Fix Zole worked well for my aquarium treatment needs.

June 12, 2026
Emily K.
★★★★★

Very satisfied with Fix Flex, easy to order and received quickly.

June 8, 2026
David L.
★★★★★

Fix Cin arrived on time and the bottle was securely packed.

June 4, 2026
Robert P.
★★★★★

Great service, Fix Pen was delivered without any issues.

May 30, 2026
Lisa T.
★★★★★

Fix Flox was exactly what I needed for my fish medicine cabinet.

May 26, 2026
Chris B.
★★★★★

Clean packaging and fast shipping for Fix Sulfa.

May 22, 2026
Amanda S.
★★★★★

Fix Zithro arrived quickly and matched the product description.

May 18, 2026
James W.
★★★★★

Good quality fish antibiotics and smooth checkout process.

May 14, 2026
Jennifer H.
★★★★★

Ordered Fix Mox and it arrived sooner than expected.

May 10, 2026
Thomas D.
★★★★★

The Fix Doxy capsules were packaged professionally.

May 6, 2026
Laura G.
★★★★★

Excellent customer service and quick delivery.

May 2, 2026
Daniel M.
★★★★★

Fix Sulfa arrived sealed and in perfect condition.

April 28, 2026
Rachel P.
★★★★★

Easy ordering process and reliable shipping.

April 24, 2026
Kevin F.
★★★★★

Fix Flox arrived exactly as advertised.

April 20, 2026
Nicole B.
★★★★★

Great experience purchasing fish antibiotics here.

April 16, 2026
Thomas B.
★★★★★

Fix Pen arrived quickly and was well protected.

April 12, 2026
Jessica R.
★★★★★

Product quality was excellent and shipping was fast.

April 8, 2026
Andrew K.
★★★★☆

Good overall experience with Fix Cin.

April 4, 2026
Olivia N.
★★★★☆

Everything arrived safely and on time.

April 1, 2026
Brian C.
★★★☆☆

Shipping took a little longer than expected but product was fine.

March 28, 2026
Karen S.
★★★★★

Fix Zole arrived quickly and was packaged very well.

March 24, 2026