---
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: "€ 39.28"
currency: EUR
in_stock: true
reviews_count: 8
category: "Kordon"
url: https://www.desertcart.gr/products/52326693-kordon-methylene-blue-disease-preventative-safe-for-freshwater-and-saltwater
store_origin: GR
region: Greece
---

# Safe for eggs, fry & sensitive species 4 fl oz potent liquid 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:** € 39.28
**Availability:** ✅ In Stock

## Summary

> 🐠 Keep your aquarium thriving—fight fungus & parasites like a pro!

## 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?** € 39.28 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.gr](https://www.desertcart.gr/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

- • **Stress-Reducing Treatment:** Helps reduce fish stress during illness, promoting faster recovery and vibrant health.
- • **Egg & Fry Friendly Formula:** Safely prevents fungal infections without harming delicate fish eggs or fry, ensuring healthy breeding success.
- • **Malachite Green Alternative:** A safer, odor-free substitute for malachite green, ideal for sensitive fish species and eco-conscious aquarists.
- • **Versatile Fresh & Saltwater Use:** Perfectly balanced for both freshwater and saltwater aquariums, making it a must-have for diverse aquatic setups.
- • **Powerful 2.303% Methylene Blue Solution:** Clinically proven to combat fungal infections and external parasites effectively.

## Overview

Kordon Methylene Blue is a 4-ounce liquid treatment designed to prevent and treat superficial fungal infections and external protozoan parasites in both freshwater and saltwater aquariums. Safe for fish eggs and fry, it reduces fish stress and serves as a reliable, odor-free alternative to malachite green, making it essential for breeders and hobbyists seeking healthy, vibrant aquatic life.

## 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 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.]

Review: Good product - Works well great stuff
Review: Medicine staple for fish keepers - This product works really well. As someone who breeds fish and also keeps Axolotls I have used this multiple times and has always done its job. Used it for preventing fungus on eggs as well as treating fungus on Axolotls gills

## 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 | 23,658 in Pet Supplies ( See Top 100 in Pet Supplies ) 280 in Aquarium Water Treatments |
| Brand | Kordon |
| Brand Name | Kordon |
| Country Of Origin | USA |
| Customer Reviews | 4.7 out of 5 stars 3,536 Reviews |
| Global Trade Identification Number | 00048054373442 |
| Included Components | BOTTLE, CAP |
| Item Form | Liquid |
| Item Type Name | KORDON # 37344 METHYLENE BLUE 4 OZ. |
| Item Weight | 9 g |
| Item form | Liquid |
| Item height | 5 inches |
| Item weight | 9 g |
| Liquid Volume | 4 Fluid Ounces |
| Liquid volume | 4 Fluid Ounces |
| Manufacturer | KORDON LLC |
| Pet Type | Fish |
| Target Species | Fish |
| UPC | 048054373442 |
| Unit Count | 118.0 millilitre |

## Product Details

- **Brand:** Kordon
- **Item form:** Liquid
- **Item weight:** 9 g
- **Liquid volume:** 4 Fluid Ounces
- **Manufacturer:** KORDON LLC

## 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).

## Customer Reviews

### ⭐⭐⭐⭐⭐ Good product
*by S***0 on 1 November 2025*

Works well great stuff

### ⭐⭐⭐⭐⭐ Medicine staple for fish keepers
*by S***Y on 9 September 2025*

This product works really well. As someone who breeds fish and also keeps Axolotls I have used this multiple times and has always done its job. Used it for preventing fungus on eggs as well as treating fungus on Axolotls gills

### ⭐⭐⭐⭐⭐ Perfect
*by E***D on 6 September 2025*

Great product

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*Product available on Desertcart Greece*
*Store origin: GR*
*Last updated: 2026-01-23*