Fish Cephalexin

Fish Cephalexin | Broad-Spectrum Aquarium Antibiotic

High-Quality Cephalexin for Bacterial Infections in Fish

Fish Cephalexin, also known as Fish Flex, is a trusted broad-spectrum antibiotic formulated to treat bacterial infections in aquarium fish. It is commonly used to combat wounds, fin rot, columnaris, and other aquatic infections, ensuring optimal fish health in both freshwater and saltwater aquariums.

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Available Variants

✔ Fish Flex 250mg – 100 Capsules – Great for treating mild bacterial infections.
✔ Fish Flex Forte 500mg – 100 Capsules – Higher dosage for stronger bacterial infections.
✔ Fish Flex 250mg – 100 Capsules (2 Pack) – Extra supply for ongoing treatments and larger aquariums.

Why Choose Fish Cephalexin?

✔ Broad-Spectrum Antibiotic – Effectively treats wounds, fin rot, columnaris, and other gram-positive & gram-negative bacterial infections.
✔ Safe for Aquarium Use – Designed to eliminate harmful bacteria while maintaining a balanced aquatic environment.
✔ Multiple Strength Options – Available in 250mg and 500mg capsules for different treatment needs.
✔ Trusted Quality – Manufactured under strict quality control standards for purity and effectiveness.

Dosage Instructions

✔ Add 1 capsule (250mg or 500mg) per 10 gallons of aquarium water.
✔ Repeat every 24 hours for 5-10 days, depending on the severity of the infection.

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.

Fish Cephalexin – Curing Fin and Tail Rot

Ragged, infected tail in a koi with fin rot: This image shows a koi’s caudal fin with extensive necrotic damage and inflammation extending into the tail base (peduncle). The fin rays are exposed and much of the fin tissue is missing, with red infection reaching the body scales. Fish Cephalexin (a first-generation cephalosporin) is an antibiotic that may be used for such common bacterial infections in fish. It is primarily effective against gram-positive bacteria and some gram-negatives that cause fin rot and body sores. By dosing the aquarium or food with cephalexin, hobbyists aim to control the bacterial load on the damaged fins. This antibiotic’s bactericidal action helps clear mild to moderate fin and tail rot infections, allowing new fin tissue to regrow at the edges once the infection is eliminated. It’s important to also improve water quality and reduce stress, as fin rot often strikes stressed fish.