--- product_id: 52326693 title: "Kordon Methylene Blue Disease Preventative – Safe for Freshwater & Saltwater Aquariums, Prevents Fungal Infections & Treats Parasites, Reduces Fish Stress, 4-Ounces" brand: "kordon" price: "¥5365" currency: JPY in_stock: true category: "Kordon" url: https://www.desertcart.jp/products/52326693-kordon-methylene-blue-disease-preventative-safe-for-freshwater-and-saltwater store_origin: JP region: Japan --- # Safe for eggs, fry & all fish types 4 oz potent liquid formula Fights fungal & protozoan infections Kordon Methylene Blue Disease Preventative – Safe for Freshwater & Saltwater Aquariums, Prevents Fungal Infections & Treats Parasites, Reduces Fish Stress, 4-Ounces **Brand:** kordon **Price:** ¥5365 **Availability:** ✅ In Stock ## Summary > 🐠 Keep your aquarium thriving—because your fish deserve the best defense! ## Quick Answers - **What is this?** Kordon Methylene Blue Disease Preventative – Safe for Freshwater & Saltwater Aquariums, Prevents Fungal Infections & Treats Parasites, Reduces Fish Stress, 4-Ounces by kordon - **How much does it cost?** ¥5365 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/52326693-kordon-methylene-blue-disease-preventative-safe-for-freshwater-and-saltwater) ## Best For - kordon enthusiasts ## Why This Product - Trusted kordon brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Malachite Green Alternative:** A safer, odor-free option for fungus control, perfect for conscientious aquarium managers. - • **Dual-Action Parasite Defense:** Effectively targets ich, chilodonella, and costia, reducing fish stress and boosting tank vitality. - • **Easy-to-Use Liquid Treatment:** Simply dilute and add to your tank—no complicated steps, just reliable protection. - • **Safe for Sensitive Fish & Fry:** Gentle enough to protect delicate fish eggs and fry, ensuring healthy aquatic generations. - • **Powerful 2.303% Methylene Blue Solution:** Clinically proven to combat fungal infections and parasites without harsh chemicals. ## Overview Kordon Methylene Blue is a 4-ounce liquid treatment designed to prevent and treat superficial fungal infections and external protozoan parasites in freshwater and saltwater aquariums. Safe for fish eggs and fry, it serves as a gentle yet effective alternative to malachite green, reducing fish stress and promoting a healthy aquatic environment. ## Description Product Description Methylene blue is effective against superficial fungal infections of fishes. The drug may be used as an alternative to malachite green for the control of fungus when it is known that the fish to be treated are sensitive. Methylene blue is safe for use with fish eggs and fry for the prevention of fungal infections. As a secondary use, it is effective against some external protozoans, such as ich, chilodonella and costia. Ingredients Methylene Blue is stable indefinitely in the 2.303% solution P.when('A').execute(function(A) { A.on('a:expander:toggle_description:toggle:collapse', function(data) { window.scroll(0, data.expander.$expander[0].offsetTop-100); }); }); Directions [GENERAL INSTRUCTIONS: Dilute and add the product to the aquarium water. Specific steps or dosage amounts are not provided in the given product information.] See more ## Features - Kordon methylene blue 4oz - Methylene blue is effective against superficial fungal infections of fishes - The drug may be used as an alternative to malachite green for the control of fungus ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B00025646W | | Allergen Information | Odor-Free | | Best Sellers Rank | 15,591 in Pet Supplies ( See Top 100 in Pet Supplies ) 174 in Aquarium Water Treatments | | Brand Name | Kordon | | Country Of Origin | USA | | Customer Reviews | 4.7 4.7 out of 5 stars (3,672) | | Global Trade Identification Number | 00048054373442 | | Included Components | CAP, BOTTLE | | Item Form | Liquid | | Item Type Name | KORDON # 37344 METHYLENE BLUE 4 OZ. | | Item Weight | 4 Ounces | | Liquid Volume | 4 Fluid Ounces | | Manufacturer | KORDON LLC | | Manufacturer Part Number | 048054373442 | | Model Number | MODEL-37344 | | Number of Items | 1 | | Pet Type | Fish | | Target Species | Fish | | UPC | 048054373442 | | Unit Count | 118.0 millilitre | ## Product Details - **Brand:** Kordon - **Item form:** Liquid - **Item weight:** 4 Ounces - **Liquid volume:** 4 Fluid Ounces - **Unit count:** 118.0 millilitre ## Images ![Kordon Methylene Blue Disease Preventative – Safe for Freshwater & Saltwater Aquariums, Prevents Fungal Infections & Treats Parasites, Reduces Fish Stress, 4-Ounces - Image 1](https://m.media-amazon.com/images/I/61Ueqt3BcYL.jpg) ## Questions & Answers **Q: Has anyone used this for fin rot and does it work well?** A: Use a few drops of this with a tsp of Epson salt per gallon and your fishy will heal. The methylene blue will stick to wound to provide oxygen to promote healing. Change 1/3 of the water per week. **Q: Is this solution good for microscope labs?** A: heck yeah! **Q: Can someone tell me if there are any additional ingredients ( preservatives,food colorings,additives,etc.) in this product?** A: label does not list any addl ingredients. Does state for aquarium fish use only. Not for human or food fish use. **Q: How much do you use per gal?** A: Please aquarium use, please follow the directions on the bottle, which says 1 tsp in 10 gallons produces a 3ppm solution. For 1 gallon, one tenth of a teaspoon is 0.5 mL, or about 10 drops. For other uses, please be aware that this is not a 1% solution. The manufacturer states that this is a 2.303% solution. This means that each drop contains 1.15mg (not 0.5mg). ## Frequently Bought Together - Kordon Methylene Blue Disease Preventative – Safe for Freshwater & Saltwater Aquariums, Prevents Fungal Infections & Treats Parasites, Reduces Fish Stress, 4-Ounces - Kanaplex, 5 g(0.18 oz) - API AQUARIUM SALT Freshwater Aquarium Salt 36-Ounce Box --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.jp/products/52326693-kordon-methylene-blue-disease-preventative-safe-for-freshwater-and-saltwater](https://www.desertcart.jp/products/52326693-kordon-methylene-blue-disease-preventative-safe-for-freshwater-and-saltwater) --- *Product available on Desertcart Japan* *Store origin: JP* *Last updated: 2026-09-21*