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API AQUARIUM SALT Freshwater Aquarium Salt 36-Ounce Box

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Availability: Only 4 left in stock, order soon!
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Arrives Sunday, Jul 27
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Size: 36 oz


Style: Aquarium Treatment


Features

  • Contains one (1) API AQUARIUM SALT Freshwater Aquarium Salt 36-Ounce Box

Description

A lack of electrolytes in aquarium freshwater may cause serious health problems for freshwater fish. API AQUARIUM SALT supplies electrolytes to improve fish respiration. Made from evaporated sea water and containing natural active ingredients such as a natural fish tonic, API AQUARIUM SALT promotes the overall health of your fish by improving their gill function and reducing stress in a freshwater aquarium. This all-natural salt provides the essential electrolytes fish need for the uptake of oxygen and release of carbon dioxide and ammonia through the gills. API AQUARIUM SALT should only be added to reduce stress during new freshwater aquarium setup and water changes or to promote disease recovery when solving specific fish health issues. Use API AQUARIUM SALT when setting up a new freshwater aquarium, when changing water or treating disease. Make sure to take extra care when using salt with live plants, as some plants may be sensitive. With API Aquarium products, it’s easy to keep a beautiful saltwater, freshwater or reef aquarium. For over 50 years, API has been creating innovative, research-driven solutions that make it easier to care for your fish and aquarium. API Aquarium Treatment Supplies are designed to work in conjunction with each other to provide best results to control algae, promote healthy bacterial growth and help control and cure fish diseases and conditions such as ich and fin rot. They work to provide a safe, hospitable environment for fish such as tropical community fish, cichlids, goldfish and more. With API, you can spend more time admiring your fish, and less time scrubbing your tank. Make sure to use all products as directed in order to ensure the best results.

Brand: API


Item Weight: 2.2 Pounds


Item Form: Liquid


Target Species: Fish


Manufacturer: Mars Fishcare


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 2.75 x 2.75 x 9 inches; 2.2 Pounds


Item model number ‏ : ‎ 106B


Department ‏ : ‎ Unisex-Adult


Date First Available ‏ : ‎ June 15, 2004


Manufacturer ‏ : ‎ Mars Fishcare


Best Sellers Rank: #4,888 in Pet Supplies (See Top 100 in Pet Supplies) #2 in Fish Medication & Health Supplies


#2 in Fish Medication & Health Supplies:


Customer Reviews: 4.7 4.7 out of 5 stars 22,980 ratings


Item Weight: 2.2 pounds


Department: Unisex-Adult


Manufacturer: Mars Fishcare


Item model number: 106B


Date First Available: June 15, 2004


Item Package Dimensions L x W x H: 8.86 x 2.91 x 2.83 inches


Item Dimensions LxWxH: 2.75 x 2.75 x 9 inches


Item Weight: 2.2 Pounds


Brand Name: API


Target Audience Keyword: algae-eaters, bottom-feeder-fish, mollusks, goldfish, octopuses, snails, fish, cichlid-fish, sharks, rays, invertebrate-fish, betta-fish


Directions: Use API Aquarium Salt when setting up a freshwater aquarium or fish bowl, when changing water, or when treating fish disease. Add 1 rounded tablespoon for every 5 U.S. gallons (20 L), or ½ rounded teaspoon for every U.S. gallon (4 L) of aquarium water. Note Aquarium salt does not evaporate and is not filtered out, so it should only be added with each water change. Care should be taken when using salt with live plants, as some plants may be sensitive. Tip API Aquarium Salt is beneficial when treating fish disease, particularly parasitic infections. For best results, use API Aquarium Salt with API General Cure or API Super Ick Cure.


Country of Origin: United States


Model Name: AQUARIUM SALT-QT (33 OZ)


Color: color multi natural


Size: 36 oz


Material: See description


Care Instructions: Disposable


Number of Items: 1


Style: Aquarium Treatment


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Jul 27

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.

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Similar Products

Top Amazon Reviews

    • Essential for Freshwater Aquariums – Must-Have for Healthy Fish!
Size: 67 oz Style: Aquarium Treatment
I’ve been using the API Aquarium Salt for my freshwater aquarium for quite some time now, and I’m thoroughly impressed with the results. Here’s why I’m giving this product a full 5-star review: 1. Promotes Fish Health: This aquarium salt is great for promoting the overall health of my fish. I’ve noticed an improvement in the vitality and color of my fish, especially when used during water changes or to help treat minor illnesses. The salt provides essential electrolytes that help maintain osmotic balance and promote a healthy immune system for the fish. 2. Works as a Healing Aid: I’ve used this salt to treat minor ailments in my fish, such as stress or injuries. It’s been especially effective in helping fish recover from small cuts or scrapes. I follow the instructions, and it seems to work wonders in speeding up recovery and reducing stress levels in my tank. It’s also helpful when acclimating new fish to the tank environment. 3. Perfect for Freshwater Aquariums: I’ve used other salt products in the past, but this one stands out for its quality and effectiveness specifically for freshwater aquariums. It dissolves easily and doesn’t cloud the water, which is a huge plus. The water quality remains stable, and the salt doesn’t cause any harm to my plants, which is important since I have a planted tank. 4. Safe and Easy to Use: This product is easy to measure and dose according to the size of my aquarium. I appreciate the clear instructions on the box, which helps me ensure I’m using the right amount. I also like that it doesn’t affect the pH of the water in a harmful way. I’ve had no issues with the salt causing unwanted spikes in my tank's water parameters. 5. Great Value for the Price: The 67-ounce box is a great value for the price. It lasts a long time, as you only need to use a small amount for each water change or treatment. Given the quality of the product and how much it improves the health of my fish, this is definitely worth the investment. 6. Packaging May Vary, But the Quality Remains the Same: Although the packaging may vary from time to time, the quality of the salt remains consistent. I’ve used this product several times, and every time, it’s been effective and high quality. Final Thoughts: The API Aquarium Salt is a must-have for any freshwater aquarium enthusiast. Whether you’re looking to improve the health of your fish, treat minor injuries, or simply maintain a stable environment, this salt does it all. I highly recommend it to anyone with a freshwater aquarium! 💯 Highly recommended – a great addition to your aquarium care routine for healthy fish! ... show more
Reviewed in the United States on February 17, 2025 by Tino Bruno
    • It’s Salt. And It’s Glorious.
Size: 36 oz Style: Aquarium Treatment
It’s salt. For fish. What more can I say? My fish aren’t throwing a party or anything, but they do look mildly impressed. Clears things up, keeps them healthy, and they haven’t staged a tiny underwater protest since I started using it. So that’s a win. If your fish are being dramatic, toss in a little of this and suddenly they’re gliding around like they’ve got a spa day booked. 10/10 — it’s salty and it works. ... show more
Reviewed in the United States on July 2, 2025 by QuantumWaffle
    • Helped my sick fish
Size: 36 oz Style: Aquarium Treatment
I used it when my fish were sick. It seemed to help
Reviewed in the United States on June 27, 2025 by James
    • Trusted Medicinal Aid for Freshwater Fish
Size: 67 oz Style: Aquarium Treatment
I’ve been using API Aquarium Salt for years, and it’s my go-to when treating sick or stressed freshwater fish. It’s a great value and works exceptionally well as a medicinal resource—especially for conditions like fin rot, minor infections, and general healing support. If illness is detected, this is my first round of defense. It’s simple, effective, and reliable. Highly recommend keeping a box on hand. ... show more
Reviewed in the United States on May 23, 2025 by Stevicus
    • Used to help Betta fin rot, minor complaints (Betta fin rot information included if you need help!)
Size: 67 oz Style: Aquarium Treatment
I purchased this API aquarium salt for it's healing properties in my freshwater Betta tank. He was coming down with a tiny section of fin rot because of poor water quality for a short period of time. This, along with very frequent 25%-50% water changes helped heal his fin rot. (The water changes alone may have worked fine, but I wanted to add salt for extra help in regrowth.) I really only have 2 complaints: 1- The granules vary, but some are quite large. Even by adding them to a small cup of boiling water and stirring frequently it took several minutes to properly dissolve. If not dissolved properly and added gradually it can burn your fish! 2- The directions are not very clear. They are listed in 3 languages, so that's nice, but there is plenty of room for more clarity on dosing your tank. (The product label is on 2 of the 4 sides so they could actually use another side for information to add clarity.) It states that you can either add 1 rounded tablespoon for every 5 gallons OR 1/2 rounded teaspoon for every gallon. The fist measurement gives you a 1 tbsp to 5 gallon ratio while the second measurement give you a 0.83 tbsp to 5 gallon ratio. I guess it's trying to be helpful for those with a tiny bowl or small hospital tank??? It mentions NOTHING about dissolving the salt first or adding it gradually. If you are treating your fish and don't happen to learn that in your own research, then you may end up just plopping the measurement into your tank and harming your fish. ***I do appreciate that it mentions that some live plants may not tolerate the salt. I chose to risk it and many did ok. They didn't grow much, but didn't seem harmed. A few did lose leaves and kinda melt away though. I simply removed those that were not tolerating the salt for the time being. ***I also appreciated the packaging mentioning that the salt does not evaporate so be careful not to compound it. For example, when I did a 25% water change, I dissolved and added 25% of the salt I had previously dosed my tank with to the new dechlorinated water. Compared to other retailers the price is good considering the volume you get. Plus the convenience of not going to a store is nice. NOTE ON TREATING BETTA FIN ROT: (Just thought I'd add this in hope that it might be helpful for someone.) Fin rot is common, so don't feel horrible if you are dealing with it. Doing lots of research before any treatment is very important! Anyone can type anything on the internet that information will pop up in a google search. Read lots of different opinions, watch many reputable/informative videos and do your best to understand why your Betta has fin rot in the first place. If you don't have a heater or filter this is the first change your should make when combatting fin rot. All Bettas (even healthy ones) with benefit from these tank additions. (If your house temperature NEVER falls below 78F you may not need need a heater, but most of us do for at least part of the year. It can easily be unplugged or removed when not needed.) Bettas don't like a strong current so a sponge filter works great. If you have a filter that is built into your aquarium or came with a set, there probably an easy way to baffle it for your Betta's comfort. I added an aquarium sponge to the output of mine. Your could be biting it's own fin which looks like bites taken out opposed to a fraying or melting of the fins. This often happens on the caudal (think tail) fins pretty much in line with where your Betta's mouth could reach. You may even observe your Betta seemingly "chase its tail." My research tells me this often happens when a Betta is unhappy so consider if your tank is large enough. Betta's enjoy stimulation so a Betta leaf, hide and silk plants are an easy addition to try if you don't already have them. The fin damage could be caused by sharp objects in the tank. This may look like a tattered or ripped fin. Betta fins are very delicate. It's good to check all decorations thoroughly by rubbing your fingers over them. You can possibly alter them to make them safe (like sanding down a rough area of driftwood) but be sure that only soft items are in your tank. Even some plastic plants may be damaging your Betta's fins so many people recommend silk or live plants only. Unclean water may have caused your fin rot. Even if it looks clear to you, it may be full of harmful ammonia, nitrites or nitrates. If you don't have a test kit, investing in one will help keep your Betta healthy. The API master test kit provides LOTS of tests and is very accurate. For me, I learned that I was not cleaning my tank the best that I could. I house 1 male Betta and 2 Nerite snails in a 5 gallon planted tank. Nerite snails help with algae, but they also poop a lot, so there was lots of animal waste my tank. Because I have a planted tank and was trying to allow some plants to carpet the bottom, I did not agitate my substrate enough when cleaning. I was also not consistent with my weekly water changes when work got busy. Big mistakes that led to a little fin rot. Along with 25% weekly water changes to reduce waste it is important to gravel vac the detritus up from your tank so that bad bacteria does not grow in your substrate. Use your siphon to press down into the substrate. Once you see lots of substrate getting pulled up (along with the detritus) lift the siphon a few inches out of the substate and give it a wiggle. This should release the substrate but allow the detritus to continue up the tubing. (If substate gets caught and slows down suction it can easily be removed by taking out your siphon and piking it with a clean wooded skewer.) If you are working around plants, do this method to the exposed substrate only. Wiggle the vac or use a clean/unused wooden chopstick or skewer to agitate around the substate of your plant. This will make the detritus start to float into the water and you can suck it up there. I also find it helpful to take a new toothbrush that I have designated for tank cleaning to the leaves of my plants. I noticed some brown algae (diatom) buildup forming on them. I initially thought they may be dying, but the brown layer came off easily and once removed it helped them grow better. On smaller leaves I just gently rubbed it off with my fingers. I use the same brush to scrub off my driftwood. You can use it on the inside glass of your aquarium too if you have a large buildup of algae, but if not then you don't need to. I have moss glued to my driftwood so I use my hands to agitate that and sometimes pull or trim off excess or weakened growth. This helps encourage new growth. I plop any removed moss into an open mason jar full of dechlorinated water and set it on the window sill to grow more fresh green algae over a month or so. Sometimes I replace that water and sometimes I top it off with a splash of old aquarium water for some plant nutrients. It is also important to note that if you have any uneaten food (pellets that fall or messy bits from a frozen food feeding) you should pull out your siphon and remove them within a few minutes. They will pollute your tank and cause problems for your fish (and you). Sometimes you have to learn the hard way, but cleaning your tank is often more involved than just scooping out some water once in a while! Good luck with your fin rot and don't forget to do your research! ... show more
Reviewed in the United States on August 21, 2019 by Alexa M.
    • Fully meet expectations.
Size: 36 oz Style: Aquarium Treatment
Fully met expectations.
Reviewed in the United States on June 23, 2025 by Amazon Customer
    • Good Stuff
Size: 36 oz Style: Aquarium Treatment
Good all around tonic for scaled aquarium fish. Ive used it for years. Live bearers love it as a staple.
Reviewed in the United States on June 8, 2025 by Dr. Freeman
    • Does what it should
Size: 36 oz Style: Aquarium Treatment
This is safe aquarium salt that I have used many times without a problem, I highly recommend it for your fish!
Reviewed in the United States on May 17, 2025 by Nicholas

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