• Fish Penicillin 500mg 100 Tablets 
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Fish Antibiotic

Fish Penicillin 500mg 100 Tablets Fish Antibiotics

$89.99 USD
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Check The Latest Expiration

Fish Antibiotics Expiration Dates

Updated: 04/09/2026

At FishAntibiotic.com, we understand the importance of using fresh and reliable fish antibiotics for aquarium and ornamental fish. Monitoring expiration dates helps ensure product effectiveness and proper aquarium care.

This page is regularly updated to provide accurate information on commonly used fish antibiotics, including Fish Mox, Fish Flex, Fish Doxy, Fish Flox, Fish Zole, and Fish Sulfa. Use this reference to compare your current products and maintain safe treatment practices.

Why Expiration Dates Matter

  • Maintains effectiveness of fish antibiotics
  • Supports safe and consistent treatment
  • Helps avoid reduced potency in older products

Fish Antibiotics Expiration List

  • Fish Mox (Amoxicillin) 500mg – 100 Capsules: Expires 08/2028
  • Fish Mox (Amoxicillin) 250mg – 100 Capsules: Expires 05/2028
  • Fish Zole (Metronidazole) 250mg – 60 Tablets: Expires 12/2027
  • Fish Zole (Metronidazole) 500mg – 60 Tablets: Expires 02/2028
  • Fish Flex (Cephalexin) 250mg – 100 Capsules: Expires 04/2027
  • Fish Flex (Cephalexin) 500mg – 100 Capsules: Expires 06/2028
  • Fish Doxy (Doxycycline) 100mg – 30 Capsules: Expires 02/2027
  • Fish Doxy (Doxycycline) 100mg – 60 Capsules: Expires 06/2027
  • Fish Pen (Penicillin) 500mg – 30 Tablets: Expires 06/2027
  • Fish Pen (Penicillin) 500mg – 60 Tablets: Expires 06/2027
  • Fish Flox (Ciprofloxacin) 500mg – 30 Capsules: Expires 04/2028
  • Fish Flox (Ciprofloxacin) 500mg – 60 Capsules: Expires 04/2028
  • Fish Sulfa (SMZ-TMP) 960mg – 30 Tablets: Expires 12/2028
  • Fish Sulfa (SMZ-TMP) 960mg – 60 Tablets: Expires 12/2028
  • Fish Zithro (Azithromycin) 250mg – 30 Tablets: Expires 06/2028
  • Fish Cin (Clindamycin) 150mg – 100 Capsules: Expires 08/2027
  • Fish Flucon (Fluconazole) 200mg – 10 Capsules: Expires 02/2028

Important Information

  • For aquarium and ornamental fish use only
  • Not for fish intended for human consumption
  • Always store products in a cool, dry place
  • Check expiration dates before use

Stay Updated

We recommend reviewing this page regularly, as expiration dates are updated based on the latest available inventory. Keeping your fish antibiotics current helps ensure effective aquarium care and reliable treatment outcomes.

Accepted payment methods
  • ✔ Free Shipping on All Orders Over $50
  • ✔ Guaranteed Fresh Stock with Latest Expiration Dates 2028+
  • ✔ Fast, Same-Day Shipping Available Before 1 PM CST

Shipping and Return

Shipping & Returns

At FishAntibiotic.com, we aim to provide a reliable shopping experience with clear shipping and return policies. Please review the information below before placing your order.

Shipping Policy

  • Shipping Area: We currently ship within the United States only.
  • Processing Time: Orders are typically processed within 1–2 business days (excluding weekends and holidays).
  • Shipping Carriers: Orders are shipped via USPS and FedEx.
  • Delivery Time: Standard delivery typically takes 3–7 business days depending on location.
  • Shipping Costs: Calculated at checkout based on destination and selected shipping method.

Order Tracking

Once your order is shipped, a tracking number will be sent to your email. This allows you to follow your shipment during transit.

Shipping Delays

Delivery times are estimates and may be affected by factors such as weather conditions, holidays, or carrier-related delays. We appreciate your understanding.

Return Policy

Due to the nature of our products, we do not accept returns on opened or used items. This policy ensures product integrity and safety for all customers.

  • Returns may be accepted for unopened items in original condition.
  • Return requests must be made within 7 days of delivery.
  • Items must be unused and in their original packaging.

Non-Returnable Items

  • Opened or used products
  • Items not in original condition
  • Products returned after the allowed return window

Damaged or Incorrect Orders

If your order arrives damaged, defective, or incorrect, please contact us within 48 hours of delivery. We will review the issue and provide a suitable resolution.

Refunds

Approved returns will be processed after inspection. Refunds are issued to the original payment method. Processing times may vary depending on your payment provider.

Need Assistance?

If you have any questions regarding shipping or returns, please contact our support team:

  • Email: fishantibiotic.help@gmail.com
  • Phone: 12345667778
  • Address: 1309 Sheridan Avenue, Cody Wyoming 82414, United States

Fish Pen 500 (Penicillin) Fish Antibiotics 500mg Tablets – 100 Count

Fish Pen 500 is a penicillin-based fish antibiotic formulated to support the treatment of bacterial infections in aquarium fish. This 100 count bottle provides a reliable solution for managing gram-positive bacterial conditions commonly found in freshwater and saltwater environments.

Penicillin is one of the most established antibiotics used in fish care, helping to control infections at early stages and prevent the spread of disease within the aquarium.

Common Uses in Aquarium Fish

  • Early-stage bacterial infections
  • Fin and tail rot (early phase)
  • Skin lesions and ulcers
  • Gill infections
  • Gram-positive bacterial infections

Dosage & Directions

Use one tablet (500mg) per 10–20 gallons of aquarium water. Crush and dissolve the tablet before adding to the tank. Repeat treatment every 24 hours for 5–7 days depending on severity.

Important Guidelines

  • For aquarium and ornamental fish use only
  • Not for fish intended for human consumption
  • Best used in early infection stages
  • Monitor fish behavior during treatment

Storage Instructions

Store in a cool, dry place away from moisture and direct sunlight. Keep container tightly sealed.

FAQ

What does Fish Pen 500 treat?
It is used for gram-positive bacterial infections, including early fin rot, skin infections, and gill issues.

When should penicillin be used?
It is most effective during early stages of infection before conditions become severe.

Can it be used in all aquariums?
Yes, it is suitable for freshwater and saltwater aquariums when used as directed.

How is it administered?
Crush and dissolve the tablet in aquarium water for treatment.