Fish Doxycycline | Trusted Treatment for Aquarium Infections

Premium Doxycycline Antibiotics for Fish Health

Fish Doxycycline, also known as Fish Doxy, is a broad-spectrum antibiotic formulated to combat bacterial infections in aquarium fish. This trusted fish antibiotic is commonly used to treat fin rot, swim bladder disease, and other bacterial illnesses, helping to restore fish health in both freshwater and saltwater aquariums.

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Available Variants

✔ Fish Doxy 100mg – 30 Capsules – Ideal for treating mild bacterial infections.
✔ Fish Doxy 100mg – 60 Capsules – Extended supply for continued treatment.
✔ Fish Doxy Powder Packets – 12 Count – Easy-to-use single-dose packets.
✔ Fish Doxy Powder Packets – 60 Count – Bulk option for multiple treatments.

Why Choose Fish Doxycycline?

✔ Broad-Spectrum Antibiotic – Effectively treats fin rot, swim bladder disease, and bacterial infections.
✔ Multiple Strength & Form Options – Available in capsules and powder packets for versatile treatment applications.
✔ Safe for Aquatic Use – Formulated to eliminate harmful bacteria while maintaining aquarium health.
✔ Trusted Quality – Manufactured under strict quality standards to ensure purity and effectiveness.

Dosage Instructions

✔ Add 1 capsule (100 mg) per 10 gallons of aquarium water.
✔ Repeat every 24 hours for 5-10 days, depending on infection severity.

Usage Tips & Cautions

✔ Remove activated carbon filters during treatment for maximum effectiveness.
✔ Perform 20-25% water changes between doses to maintain water quality.
✔ Not for human use.

Related Products

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• Fish Mox - Amoxicillin 500mg (100 Capsules)
• Fish Flox - Ciprofloxacin 500mg (60 Capsules)
• Fish Sulfa Forte - Sulfamethoxazole 800mg, Trimethoprim 160mg (100 Tablets)
• Fish Pen - Penicillin 500mg (30 Tablets)

Fish Doxycycline – Fighting Advanced Tail Rot

Severe tail rot (peduncle disease) in a koi: In advanced fin rot, the infection can progress to the fish’s caudal peduncle (tail base), causing deep ulceration and inflammation where the fin meets the body​. The fins may be almost completely eroded with red, exposed tissue. Fish Doxycycline is a broad-spectrum antibiotic (tetracycline class) effective against many gram-negative and gram-positive bacteria​. It is often used for stubborn infections like advanced fin/tail rot, body ulcers, and even systemic infections. Doxycycline works by inhibiting bacterial protein synthesis, thereby controlling the infection. Hobbyists report it helps conditions like infected fin bases, “saddleback” ulcers, and even pop-eye, by eliminating sensitive bacteria and reducing inflammation