Fish Penicillin 500mg 30-Capsules

Complete Collection

Browse All Fish Antibiotics

Add any mix of products to your cart. Volume discounts apply automatically.

Fish Mox 500mg - 100 count

$59.49 $64.99

✓ In Stock

Fish Mox 500mg - 30 count

$35.99 $39.99

✓ In Stock

Fish Doxy 100mg 100-Tablets

$79.99 $83.87

✓ In Stock

Fish Ceph 500mg 100-Capsules

$69.99 $74.99

✓ In Stock

Bird Zithro 250mg - 30ct. tablets

$89.99 $96.99

✓ In Stock

Fish Mox 250mg 100-Capsules

$48.99 $53.99

✓ In Stock

Fish Zole 250mg 100-Capsules

$59.99 $60.99

✓ In Stock

Fish Zole 500mg 100-Capsules

$79.99 $80.99

✓ In Stock

Fish Mox 250mg - 30 count

$34.34 $37.34

✓ In Stock

Fish Ceph 250mg 100-Capsules

$54.99 $63.99

✓ In Stock

Fish Penicillin 500mg 60-Capsules

$68.99 $69.98

✓ In Stock

Fish Penicillin 500mg 30-Capsules

$48.61 $49.99

✓ In Stock

Fish Doxy 100mg 30-Tablets

$59.99 $64.99

✓ In Stock

Fish Flox 500 - 30 Capsules

$56.89 $59.99

✓ In Stock

Fish Doxy (Doxycycline) 100 mg 100 Capsules Fish Antibiotics - 2 Pack

$147.98 $179.98

✓ In Stock

Fish Clin 150 - 100 Capsules

$79.99 $82.80

✓ In Stock

Fish Sulfa 960mg 60-Tablets

$79.99 $80.99

✓ In Stock

Fix Flox 500 - 60 Capsules

$104.99 $109.99

✓ In Stock

Best Seller Fish Antibiotics Package - 5 Products

$415.00 $460.00

✓ In Stock

FIX MOX & FIX FLOX Essential Care Bundle

$129.99 $164.48

✓ In Stock

Fish Ceph 500mg 30-Capsules

$37.99 $38.99

Out of Stock

Fish Ceph 250mg 30-Capsules

$39.99 $43.99

Out of Stock

Bird Zithro 250mg - 12ct. tablets

$54.99 $56.99

Out of Stock

Fish Sulfa 960mg 30-Tablets

$59.99 $63.99

✓ In Stock

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Value Bundles

Pre-made bundles for complete aquarium care. Bigger savings, fewer shipments.

Best Value

Fish Doxy (Doxycycline) 100 mg 100 Capsules Fish Antibiotics - 2 Pack

Fish Doxy (Doxycycline) 100 mg 60 Capsules Fish Antibiotics - 2 Pack

$147.98$179.98

You save $32.00

Best Value

Best Seller Fish Antibiotics Package - 5 Products

Best Seller Fish Antibiotics Package - 5 Products This Best Fish Antibiotics Seller Package is designed to provide co...

$415.00$460.00

You save $45.00

Best Value

FIX MOX & FIX FLOX Essential Care Bundle

Professional Grade Antibacterial Binome: Mox & Flox

$129.99$164.48

You save $34.49

Build Your Own Bundle

Pick any 4+ products from our collection and save $10 automatically at checkout. Mix and match any antibiotics!

Save $10+ — Auto-applied

Browse & Build Your Bundle

Customer Reviews

What Our Customers Say

4.9 out of 5 stars — based on 2,847 verified reviews
Verified by Judge.me

★★★★★

Purchased: Fish Mox 500mg

"My koi had a persistent bacterial infection. Started treatment with Fish Mox and within a week the redness cleared up completely. Arrived in 2 days."

Michael R.

Verified Buyer — May 2026

★★★★★

Purchased: Fish Doxy 100mg (100ct)

"Best price with the fastest shipping I've experienced. Product quality is identical to what I used to pay double for at the local pet store."

Sarah T.

Verified Buyer — April 2026

★★★★★

Purchased: Best Seller Package

"The bundle deal was unbeatable. Got everything I needed for my 120-gallon reef tank at a fraction of what the local fish store charges."

James K.

Verified Buyer — April 2026

★★★★★

Purchased: Fish Flox 500 (60ct)

"Quick shipping, well-packaged, exactly as described. My cichlids bounced back in days. Will definitely keep this store bookmarked."

David L.

Verified Buyer — March 2026

★★★★★

Purchased: Fish Ceph 500mg + Fish Mox 250mg

"I maintain 6 freshwater tanks. The volume discount saves me serious money compared to buying individually. Highly recommend."

Rachel P.

Verified Buyer — March 2026

★★★★★

Purchased: Fish Sulfa 960mg

"Had a rough bout of columnaris. Fish Sulfa knocked it out fast. Great prices and customer service was super responsive."

Anthony G.

Verified Buyer — February 2026

Common Questions

Frequently Asked Questions

What are fish antibiotics used for?

Fish antibiotics treat bacterial infections in ornamental and aquarium fish — fin rot, columnaris, pop-eye, dropsy, and more. They contain USP-grade active ingredients.

How do I dose fish antibiotics?

Each product includes dosing instructions. Generally, capsules are opened and powder is dissolved in a quarantine tank. Consult a vet or experienced aquarist for your specific species.

Do you offer volume discounts?

Yes! Buy 2+ items and save $4, buy 4+ items and save $10, or buy 8+ items and save $20. Mix and match any antibiotics — discounts apply automatically at checkout.

How fast is shipping?

Free shipping on all USA orders. Orders placed before 5 PM EST ship same day. Most deliveries arrive within 2-5 business days via UPS, USPS, DHL, or FedEx.

What is your return policy?

30-day money-back guarantee on all unopened products. Damaged items replaced free — send us photos within 48 hours. Contact support@thediscountpets.com.

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