Buy Now, Pay Later
As low as
$2
/ mo
Learn more
- – 4-month term
- – No impact on credit to apply
- – Instant approval decision
- – Secure and straightforward checkout
Ready to go? Add this product to your cart and select a plan during checkout.
Payment plans are offered through our trusted finance partners Klarna, Affirm, Afterpay, Zip, Apple Pay, and Google Pay. No-credit-needed leasing options through Acima may also be available at checkout.
Learn more about financing & leasing here.
Selected Option
Free shipping on this product
30-day returns
Learn more
FREE 30-day refund/replacement
To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
Availability:
Only 2 left in stock, order soon!
Arrives
Saturday, Aug 15
Recently Viewed
Size: 5 g (0.18 oz)
Features
- For use in freshwater or marine aquaria.
- Easily absorbed through both skin and gills; ingestion not required.
- Does not adversely affect the filter bed and is easily removed with carbon.
- Safely and effectively treats several fungal, and bacterial fish diseases (dropsy, popeye, fin/tail rot, septicemia).
- When used in a medicated food mix, it is excellent for treating bacterial infections in tanks that contain invertebrates.
Description
KanaPlex™ is a blended kanamycin based medication that safely and effectively treats several fungal, and bacterial fish diseases (dropsy, popeye, fin/tail rot, septicemica). Because it is absorbed by fish it is useful in treating internal infections in those situations where food is refused. It does not adversely affect the filter bed and is easily removed with carbon. To enhance palatability use with GarlicGuard™. Food may be refrozen. For use in freshwater or marine aquaria.
Brand: Seachem
Liquid Volume: 5 ml
Item Weight: 1.12 ounces
Item Form: Powder
Number of Packs: 1
Product Dimensions : 4.75 x 3.75 x 1.25 inches; 1.12 ounces
Item model number : 881
Date First Available : April 25, 2013
Manufacturer : Seachem
Best Sellers Rank: #1,833 in Pet Supplies (See Top 100 in Pet Supplies) #6 in Aquarium Water Treatments
#6 in Aquarium Water Treatments:
Customer Reviews: 4.6 4.6 out of 5 stars (3,985)
Brand Name: Seachem
Unit Count: 18 Fluid Ounces
Manufacturer: Seachem
UPC: 000116088107
Included Components: treats several fungal, and bacterial fish diseases
Model Number: 881
Manufacturer Part Number: 881
Liquid Volume: 5 ml
Item Weight: 1.12 ounces
Item Form: Powder
Pet Type: Fish
Target Species: Fish
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Saturday, Aug 15
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
- Klarna Financing
- Affirm Pay in 4
- Affirm Financing
- Afterpay Financing
- Zip Pay in 4
- Financing through Apple Pay
- Financing through Google Pay
Learn more about financing & leasing here.
Similar Products
Top Amazon Reviews
Size: 5 g (0.18 oz)
I honestly wasn’t expecting such great results, but this medication exceeded my expectations. My betta fish, Bluey, had a pretty bad case of fin rot, and his fins had several holes and damaged areas. After following the directions and completing the treatment, I started noticing new fin growth. His fins are filling back in beautifully, and the damaged areas have almost completely recovered. Even better, he’s much more active, alert, and seems happier overall. I’m so relieved I found this product. It truly helped my fish recover, and I would definitely recommend it to anyone dealing with fin rot. It made a huge difference for Bluey.
...
show more
Reviewed in the United States on June 19, 2026 by Sandra Acosta
Size: 5 g (0.18 oz)
One of the best antibiotics for fish keepers to keep on hand. It doesn’t stain or discolor the water and it is gentle on the aquarium’s bio filter. It treats a broad spectrum of illnesses and can be dosed directly into the water or soaked into the dish food and administered while feeding.
Reviewed in the United States on July 29, 2026 by Maureen Baumgartner
Size: 5 g (0.18 oz)
Over 30 one-month-old guppy fry in one of my aquariums started developing needle-like tails. In the morning, I noticed one of my fry had died overnight and several of my fry looked lethargic at the water surface with one fry floating on his side and struggling to remain upright. Now, while I'm no stranger to keeping freshwater fish, I just started keeping guppies a little over a year ago and this is the first time I've seen such a wide-spread infection with such a fast mortality rate. Admittedly, this tank in question was a bit overcrowded, since one of my female guppies gave birth a month ago with a surprisingly large batch of fry (for me at least). Since keeping guppies, finding spare tanks to keep each new batch of fry in has been a bit challenging. After testing the water for ammonia and finding close to 1ppm, I immediately separated four of the most lethargic fry into their own tank (since some of the more healthy-looking fry were trying to eat them) and spent the next two days performing large water changes. The fry only got worse, now with almost all of the fry displaying pointed needle-like tail fins even though water quality had considerably improved with 0 ammonia and nitrite. And sadly, another two fry that I had separated the first day hadn't made it. I was now left with one really sick fry (in the separate tank) and 28 less-than-active fry who looked like they were only getting sicker. A few weeks ago, I had purchased some Kanaplex to try for a just-in-case situation like this when time would be crucial. I had never used Kanaplex before, but I had lost some fish in the past because I wasn't able to get the medication quickly enough. I liked that this medication doesn't destroy the good beneficial bacteria in the filter bed, but I was very hesitant about using this in my fry tank because of how young and weak my fry were - I wasn't sure if they'd be able to handle medication. But I figured, they were already suffering and going to die if I just did nothing more than change the aquarium water, so I put some in and hoped for the best. Two days later, I already started to see some improvement. My fry were swimming more actively and I noticed some of them were starting to spread out their fins more. The lone fry in the really sick tank still looked somewhat the same to me, though he wasn't flipped over and paralyzed like many of his brothers who had died were. He was still swimming around the surface, moving his fins, so I thought that was a good sign. The best news was that I had lost no more fry since treating both aquariums. I had thought I would soon have a massive fry death on my hands, so that alone was something to celebrate. Following the instructions, I treated both tanks with the second dose of Kanaplex on the third day. Every day, the fry seemed to be doing better and better. Today on day 5, all 28 fry in the healthier tank are very active, eating as usual with fins fully expanded. Just looking at them, you would've never known they were sick! The lone fry in the separate tank is also doing very well. Just yesterday, he started eating for the first time since the infection. While his tail fin still looks somewhat pointy, the milky white film on it is nearly gone and it's no longer as clamped. I also noticed he's been spending less time on the surface and more time moving around the aquarium! Before I had little hope he'd make it and now I really do think he'll make a full recovery. I just added the third and last dose to the tank. I'm really looking forward to adding the lone fry back into the tank with his brothers and sisters. I also bought a larger aquarium to house these fry once they get bigger. Very happy with the results I've received from Kanaplex.
...
show more
Reviewed in the United States on April 8, 2016 by Christina M. Krasow
Size: 5 g (0.18 oz)
This product saved my betta fish. She was floating towards the ground a lot, she quit eating and stopped responding to me so I used this for 3 days and she’s back to the way she was! She is eating and very active.
Reviewed in the United States on July 21, 2026 by Lacie Shelton
Size: 5 g (0.18 oz)
I recommend keeping some on hand for emergencies. I moved across the state recently and it was very stressful for my Betta. She developed epistylis about 3 days later, and quickly her health started to deteriorate! I knew I had to act fast and none of the stores near me carry Kanaplex specifically, which I wanted because it was recommended to me to try first. Amazon had it to me overnight which I am eternally grateful for because my fish began to recover after 3 days of consistent dosing both to the water and in food. Now she’s back to her usual self, all signs of epistylis are gone, and I’m glad i chose kanaplex. Safety: it is an antibiotic for an aquarium. Follow the directions on the back and everything will be fine. Plant growth: can’t speak on this one. I used a hospital tank so nothing was affected. Unsure on if it’s fully plant safe; I’d recommend googling your specific plant type to see if it could be negatively affected if you plan to dose your tank. Value for money: great value. I did not need a massive container, I only have a single Betta in a 10 gal. I really only needed 3 days of treatment but planned for 1 week just in case; I still have a little under half of the container filled after using 2 full doses for the hospital tank, and roughly half a dose for mixing with food which I then froze and took out tiny pieces to thaw as I needed. I fully believe that feeding it + dosing the tank is what led to a full recovery. Final verdict: Keep some of the common antibiotics on hand for emergencies, because when something does happen it sets in quick. Now I keep this product, some methylene blue and plenty of catappa leaves on hand. My fish is healthy and alive because I caught the epistylis quick and started treatment immediately.
...
show more
Reviewed in the United States on November 29, 2025 by C&J
Size: 5 g (0.18 oz)
Product is fine. Usually works depending on the fishes resistance to it. Packaging however, leaves a lot to be desired. 1. White powder with a white spoon. It’s difficult to tell if it’s full of powder or are you looking at the bottom instead of the top? Seriously. I have realized I’ve had the spoon upside down when I’m trying to scoop the powder up. 2. All the powder is at the bottom of tube, so why put it in a long tube with a short spoon, making us tap and tip trying to get at it? Dumb.
...
show more
Reviewed in the United States on June 4, 2026 by dd
Size: 5 g (0.18 oz)
Works well!
Reviewed in the United States on August 2, 2026 by Tina
Size: 5 g (0.18 oz)
Cory’s and Angelfish have cotton mouth fungus, very contagious. This medicine works fast! Fish are feeling and looking better. My young angelfish’s cotton mouth is almost gone by second dosing. Thanks Seachem!
Reviewed in the United States on June 12, 2026 by Marc