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Kordon

Kordon Methylene Blue Disease Preventative – Safe for Freshwater & Saltwater Aquariums, Prevents Fungal Infections & Treats Parasites, Reduces Fish Stress, 4-Ounces

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Availability: In Stock.
Fulfilled by Amazon
Arrives Wednesday, Feb 11
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Features

  • 100% Quality driven Made in the USA
  • Dedicated to creating a better environment for your pet
  • Safety Guaranteed, Don't settle for Less, Use Kordon
  • AQ MEDICATIONS & REMEDIES, FW
  • Age Range Description: All Ages
  • Package Dimension : 1.27 centimeters L x 2.286 centimeters W x 12.954 centimeters H
  • Item Package weight : 0.136 kilograms

Description

KORDON 37344 Methylene Blue-General Disease Prevention Treatment for Aquarium, 4-Ounce,

Brand: Kordon


Liquid Volume: 4 Fluid Ounces


Item Weight: 9.07 g


Item Form: Liquid


Manufacturer: KORDON LLC


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 2 x 2 x 5 inches; 0.32 ounces


Item model number ‏ : ‎ MODEL-37344


Department ‏ : ‎ Unisex-Adult


Date First Available ‏ : ‎ October 2, 2001


Manufacturer ‏ : ‎ KORDON LLC


Best Sellers Rank: #5,188 in Pet Supplies (See Top 100 in Pet Supplies) #4 in Fish Medication & Health Supplies #29 in Aquarium Water Treatments


#4 in Fish Medication & Health Supplies:


#29 in Aquarium Water Treatments:


Item Weight: 0.32 ounces


Department: Unisex-Adult


Manufacturer: KORDON LLC


Item model number: MODEL-37344


Date First Available: October 2, 2001


Item Package Dimensions L x W x H: 5.91 x 1.69 x 1.57 inches


Item Dimensions LxWxH: 2 x 2 x 5 inches


Item Weight: 9.07 g


Brand Name: Kordon


Target Audience Keyword: fish


Directions: 1. Use Methylene Blue to control fungus on eggs. 2. Utilize it to assist the transport of oxygen in fish poisoned by cyanide and nitrite ion. 3. Apply Methylene Blue to control some external protozoan parasites of fishes. 4. Dilute the solution with water according to the recommended ratio. 5. Add the diluted solution to the aquarium.


Country of Origin: United States


Model Name: MODEL - 37344


Color: CLEAR BLUE


Size: 4 Ounce


Material: Plastic


Age Range Description: all ages


Care Instructions: Store in a cool, dry place. Do not freeze.


Number of Items: 1


Breed Recommendation: All Breed Sizes


Included Components: KORDON #37344 Methylene Blue-General Disease Prevention Treatment for Aquarium, 4-Ounce,


Specific Uses for Product: The use of Methylene Blue is primarily for the control of fungus on eggs, and to assist the transport of oxygen in fish poisoned by cyanide and nitrite ion. Secondary uses are for the control of some external protozoan parasites of fishes. Methylene Blue is an alternative for treatment with other medications when prevailing factors preclude the use of another medication.


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If you place your order now, the estimated arrival date for this product is: Wednesday, Feb 11

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Top Amazon Reviews

    • Fungus, not sure what's going on. Fish need extra oxygen.
Size: 4 Ounce Pattern Name: Aquarium Pond Water Treatment
Review Image by Tina Wilson Tina Wilson
Review Image by Tina Wilson Tina Wilson
Review Image by Tina Wilson Tina Wilson
Review Image by Tina Wilson Tina Wilson
Review Image by Tina Wilson Tina Wilson
Review Image by Tina Wilson Tina Wilson
Review Image by Tina Wilson Tina Wilson
Review Image by Tina Wilson Tina Wilson
Review Image by Tina Wilson Tina Wilson
I've been using methylene blue for a long time. I use it for fungus on my fish if I notice a little bit starting or if their coat starts getting a little slimy. I usually try this before I try anything else. Or if for some reason my nitrates or nitrite spike I'll use this a little bit for some added oxygen if my fish start getting stressed out or are already stressed out. This has always worked very well for me. I've never had any fish stressed out about it. No headshaking ever like what happens when I add metronidazole or praziquantal or other meds. Methylene blue has also never hurt my pond plants. I don't pour it directly in my pond. It's always been in the hospital tank. I did recently use it when I bought some water hyacinth from a pond shop. I always bring them home and put them in a container with grow lights and heat to make sure that they don't have a bunch of snails and dragonfly nymphs and whatever else there is on those things. Well, I ended up having a bunch of baby fry fish hatch from these plants. About a week later the little fry baby's started turning white and dying. I wasn't really sure what to due because I didn't want to kill these plants that I just spent a couple hundred dollars for and I didn't want to let the baby fish die. I added some methylene blue and some nitrofuranzone together with the baby fry and with the plants which also had snails, snail eggs, dragonfly nymphs on them and the white that I guess was fungus on these little baby fish I can't really tell because they were so small. I did it once left it in there for two days and then the partial water change and I didn't have any more baby fry fish die and my Hyacinth plants are still growing and still blooming. Some even flowered out purple flowers right away. So it didn't hurt them at all. I was kind of disappointed about these plants and there had to have been something on them for these baby fish to get this but not only that the guy told me that they had goldfish in with the plants. I called And asked him after all these baby fries start hatching. I think something that people should think about, and I don't know if people actually just buy plants and throw them in their ponds. I always did and I always ended up coming down with some kind of ailment around that time and I just thought it was a change in temperature, water parameters. But if the place where you buy the plants has goldfish or other fish in with them they have a fungus or bacterial infection and you bring those plants home and throw them in your pond you're going to bring that stuff into your pond. So for now on I quarantine my plants. Back to the methylene blue. It's definitely blue. I've never had it stain anything. I took pictures of what it looked like. It took pictures of my fingers after completely just dipping them in the stuff. And then the last picture I took was me washing my hands one time. It was almost completely off. Once I take a shower it's completely gone. I've never had the methylene blue stain anything that I've ever had permanently. I think that having the methylene blue around in case you have something going on and you don't know what it is is a fish lifesaver. You can at least be able to use it just in case you need to. It is better than not having anything at all. If I wouldn't have had the methylene blue on hand along with the nitrfurazone at the time I'm pretty sure all the little fish would have been dead. Because that morning when I checked on them they had nothing white on them. Later that afternoon is when I started noticing it. About four of them died. So that's my methylene blue story. I'm not sure how it would stain if you got it like on your rings or your jewelry or anything but it does eventually go away when I get it on my hands and stuff. ... show more
Reviewed in the United States on May 21, 2020 by Tina Wilson Tina Wilson
    • Saved my betta
Size: 4 Ounce Pattern Name: Aquarium Pond Water Treatment
Saved my betta from dropsy. This stuff is a life saver. It is very safe as long as you dose correctly. And my betta is happy and healthy now because of it!
Reviewed in the United States on November 30, 2025 by Kylee ward
    • Great Medicine for my Freshwater Fish
Size: 4 Ounce Pattern Name: Aquarium Pond Water Treatment
Worked great on my sick fish, kept the fish in the Methylene Blue for a few days and slowly started to do water change to ease it's transition back into normal water. Just follow the instructions and be careful not to spill as it can stain counter tops.
Reviewed in the United States on October 5, 2025 by Kevin
    • Effective, but a little leaky
Size: 4 Ounce Pattern Name: Aquarium Pond Water Treatment
It appears to work rather quickly against Saprolegnia on Koi. Note: This bottle is a little leaky, and the stuff stains like heck. Use rubber gloves and keep the bottle in a bag in a bucket, and make sure it doesn't come into contact with things you don't want blue.
Reviewed in the United States on April 7, 2025 by Brian V
    • Successful treatment
Size: 4 Ounce Pattern Name: Aquarium Pond Water Treatment
Delivered as described. The treatment was successful. For sure satisfaction from my end.
Reviewed in the United States on December 15, 2025 by Don Notts
    • Good deal
Size: 4 Ounce Pattern Name: Aquarium Pond Water Treatment
Good quality, very strong and concenntrated. Easy to use. Very cheap. Safe for fish to have the fish for 5_ 10 minutes once a day for 5 days if the fish sick. Works very fast.
Reviewed in the United States on July 11, 2025 by Mohammad Altaani
    • Great product
Size: 4 Ounce Pattern Name: Aquarium Pond Water Treatment
Keeps my fish as healthy as can be. When I get them home everyone goes into a quarantine tank treated with this product befor going into my big tank!!! Would give 10 stars if I could
Reviewed in the United States on August 17, 2025 by Tara Guest
    • Works as intended
Size: 4 Ounce Pattern Name: Aquarium Pond Water Treatment
This will last you forever, I use this to treat freshly laid fish eggs for my Cory's and Angel's to prevent fungus problems, works like a charm!
Reviewed in the United States on November 16, 2025 by Frye Kozlowski

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