# Kordon Methylene Blue 4 oz *Published: 2026-02-16 | Updated: 2026-02-16 | Source: https://shopsavvy.com/products/kordon-methylene-blue-4-oz* --- **Brand:** Kordon **Price Range:** $4.39 - $29.13 across 27 retailers ## Pros - Effectively treats fungal infections on fish eggs, koi, goldfish, and aquarium fish. - Works well for fin and tail rot as a separate bath treatment. - Safely helps with ammonia poisoning, nitrite poisoning, ich, velvet disease, and mild bacterial infections. - Proven track record of success and reliability according to multiple user experiences. - Can be used as a dip or in temporary containers for targeted treatment without harming fish. - Does not cause harm or health issues to aquatic animals when used correctly. - Useful to protect fish during shipping or fry rearing by preventing bacterial and fungal growth. - Noticeable improvement in fish behavior like swimming and eating after treatment. - Considered a safe alternative to malachite green, avoiding burning or extreme irritation. - Easy to use and supports healthy fry development and recovery. ## Cons - Stains tank surfaces, including silicone seals, making it unsuitable for direct addition to main aquariums. - Should not be used directly in the main tank as it can harm beneficial bacteria essential for aquarium health. - Works best for mildly sick fish; not effective for severely ill or damaged fish. - Does not eliminate unpleasant fishy odors from aquariums. ## Specifications | Attribute | Value | |-----------|-------| | product_name | Kordon Methylene Blue-General Disease Prevention Treatment for Aquarium | | part_number | 37344 | | size | 4-Ounce | | effectiveness | works best on non severely sick fish | | brand | Kordon | ## Last Seen Prices | Retailer | Price | Availability | Last seen | |----------|-------|-------------|-----------| | [AlotOfHome.com](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/f7yvSkXMaPILgfehBubQ?source=shopsavvy&medium=product-page) | $4.39 | In Stock | 2023-07-31 (may have changed) | | [PetMountain.com Pet Supplies](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/Ok4oJ49EyRJS9IcVrd6C?source=shopsavvy&medium=product-page) | $4.39 | In Stock | 2023-07-31 (may have changed) | | [Petproducts.com](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/XAf3CAEVYLpJ8hxyHimr?source=shopsavvy&medium=product-page) | $4.73 | In Stock | 2022-07-24 (may have changed) | | [PetMountain.com Pet Supplies](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/w1QdLq3l4Hjw9Rr5Bua2?source=shopsavvy&medium=product-page) | $4.74 | In Stock | 2022-07-24 (may have changed) | | [That Fish Place](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/SAUzQp23fGhxXR6T8ERD?source=shopsavvy&medium=product-page) | $5.79 | In Stock | 2022-07-24 (may have changed) | | [DrugSuppyStore.com](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/2wFPpDDK0zv7axXSC7Id?source=shopsavvy&medium=product-page) | $5.86 | In Stock | 2023-07-31 (may have changed) | | [Pet Life](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/b1xEeo5ZTpySufmjcV1i?source=shopsavvy&medium=product-page) | $6.27 | In Stock | 2023-07-31 (may have changed) | | [AnimalWiz.com](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/vWr6Q3nDEi7z9FuzMjng?source=shopsavvy&medium=product-page) | $6.35 | In Stock | 2022-07-24 (may have changed) | | [Port Orchard Parrots Plus](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/4MmMZBnAaaOhTKAJEUmV?source=shopsavvy&medium=product-page) | $6.99 | In Stock | 2023-07-31 (may have changed) | | [CountryMax](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/crRCKbWqgfkunvsOK6im?source=shopsavvy&medium=product-page) | $7.49 | In Stock | 2023-07-31 (may have changed) | | [Bonanza](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/3erLHGqww7M6cNrCu6JS?source=shopsavvy&medium=product-page) | $7.60 | In Stock | 2022-07-24 (may have changed) | | [Blue Fish Aquarium](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/9mulq4j7BIPBie5GC4qf?source=shopsavvy&medium=product-page) | $7.99 | In Stock | 2023-07-31 (may have changed) | | [National Pet Warehouse](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/gI0wGBEKqXxKe19hSA12?source=shopsavvy&medium=product-page) | $8.20 | In Stock | 2023-07-31 (may have changed) | | [Pet-Topia](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/sff6r9w31z0b8lxZofxr?source=shopsavvy&medium=product-page) | $8.99 | In Stock | 2023-07-31 (may have changed) | | [Southern Agriculture](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/Qkk9Qo9CrnlRjirm0jhh?source=shopsavvy&medium=product-page) | $8.99 | In Stock | 2023-07-31 (may have changed) | | [Age of Aquariums](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/kKglP9b8LHPaVKbcoCH2?source=shopsavvy&medium=product-page) | $9.99 | In Stock | 2023-07-31 (may have changed) | | [Aquatic Marine Aquarium Specialist](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/uMxR42BOqVFMdMpuhrIS?source=shopsavvy&medium=product-page) | $9.99 | In Stock | 2023-07-31 (may have changed) | | [Pets Warehouse](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/4lBFR5JM9jv9oscrLdjZ?source=shopsavvy&medium=product-page) | $9.99 | In Stock | 2023-07-31 (may have changed) | | [Super Cichlids](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/xPb3eOCqiax3MNqJPrBv?source=shopsavvy&medium=product-page) | $9.99 | In Stock | 2023-07-31 (may have changed) | | [Chewy](https://shopsavvy.com/api/redirect/products/wdkgPLQl9qp9ZKVEpyEn/offers/0bbe4259-d8fd-d72b-0a96-aaa28c069c3d?source=shopsavvy&medium=product-page) | $10.57 | In Stock | 2024-11-12 (may have changed) | [See every retailer and the full price history on ShopSavvy](https://shopsavvy.com/products/kordon-methylene-blue-4-oz) --- *About this page: ShopSavvy compares prices across thousands of retailers, aggregates expert and user reviews, and tracks price history to help you make informed buying decisions. 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