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API

API Stress Coat Aquarium Water Conditioner 16-Ounce Bottle

  • Based on 38,674 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, Sep 14
Order within 7 hours and 44 minutes
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Size: 16 fl oz


Style: Aquarium Treatment without Pump


Features

  • Contains one (1) API STRESS COAT Aquarium Water Conditioner 16-Ounce Bottle
  • Makes tap water safe and protects fish with dual-action formula
  • Removes chemicals from tap water that are harmful to fish
  • Replaces fishs protective coat damaged by handling or fish fighting with healing power of Aloe Vera extract
  • Use when adding or changing water, when adding new fish and when fish are sick or injured
  • Instructions: Add 5 ml. for each 10 gallons of aquarium water. Double the dose to replace slime coat and to repair damaged skin and fins

Description

Treat your tap water, and provide a safe environment for freshwater fish instantly and easily with API STRESS COAT Freshwater Aquarium Water Conditioner. Tap water contains chlorine, chloramines and ammonia which can cause gill and tissue damage, breathing difficulty, stress and death. API STRESS COAT Aquarium Water Conditioner works instantly as a water conditioner to remove chlorine and chloramines from tap water and neutralize heavy metals. API STRESS COAT Freshwater Aquarium Water Conditioner Treatment contains aloe vera, and it is scientifically proven to reduce fish stress by 40% and heal damaged fish tissue. This conditioner replaces the natural secretion of slime that is interrupted by handling, shipping, fish fighting, or other forms of stress and helps heal torn fins and skin wounds while promoting tissue regeneration. API STRESS COAT is recommended by professional fish handlers. With API aquarium products, it’s easy to keep a beautiful saltwater, freshwater or reef aquarium. For almost 60 years API has developed premium solutions with proven and effective results for your family and ours. API offers a range of testing kits, water conditioners, and nutritionally superior food, because we’re dedicated to making a better underwater world. They work to provide a safe, hospitable environment for fish such as tropical community fish, cichlids, goldfish and more. At API, we understand the rewards and relaxation of fishkeeping because we have a passion for fish too.

Brand: API


Liquid Volume: 0.48 liters


Item Weight: 6.4 ounces


Item Form: Liquid


Number of Packs: 1


Product Dimensions ‏ : ‎ 5 x 1 x 5 inches; 6.4 ounces


Manufacturer recommended age ‏ : ‎ 1 month and up


Item model number ‏ : ‎ 85C


Department ‏ : ‎ Unisex-Adult


Date First Available ‏ : ‎ June 15, 2004


Manufacturer ‏ : ‎ Mars Fishcare


Best Sellers Rank: #759 in Pet Supplies (See Top 100 in Pet Supplies) #3 in Aquarium Water Treatments


#3 in Aquarium Water Treatments:


Customer Reviews: 4.8 4.8 out of 5 stars (38,674)


Brand Name: API


Number of Packs: 1


Unit Count: 16 Ounce


Manufacturer: Mars Fishcare


UPC: 317163050859


Number of Items: 1


Global Trade Identification Number: 59


Item Type Name: Aquarium Water Conditioner


Model Number: 85C


Manufacturer Part Number: 85C


Liquid Volume: 0.48 liters


Item Weight: 6.4 ounces


Item Form: Liquid


Pet Type: Fish


Target Species: Fish


Allergen Information: Apple Free


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Sep 14

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

    • Not Just for Fish! Also Great for Plants!
Size: 4 fl oz Style: Aquarium Treatment without Pump
Review Image by C.J
Review Image by C.J
Review Image by C.J
I don't use this for an aquarium. In fact, I don't even have an aquarium. It was recommended by a plant expert to use in the water I use to water my plants. Hard, chlorinated water filed with chemicals is not good at all for plants and while it won't kill most of them, some of them end up unhappy over time. When I first heard about this product, I was skeptical. Could it really help with my plants? Well, upon researching, apparently so! It removes not only chlorine, which is in all tap water, it removes chloramines and heavy metals. They're all bad for fish and bad for plants as well! The price is low and I use just 2 - 3 drops with each gallon of tap water, immediately takes action. No waiting! I bought the 4 ounce size and at this concentrate, that much will last me years (and I have a lot of house plants. There's not much odor, it's clear and a little thicker than water. This is a no-brainer. I'm happy I discovered it. ... show more
Reviewed in the United States on August 2, 2026 by C.J
    • Magic in a Bottle for Your Aquarium!
Size: 16 fl oz Style: Aquarium Treatment without Pump
Having a home aquarium can be a tricky endeavor, especially when it comes to maintaining a healthy environment for your fish. This product has been a game changer for me. Firstly, the 16-ounce size is very economical. It lasts quite a while even with regular use, which is great for someone who doesn’t want to constantly repurchase supplies. The application process is straightforward and easy – just follow the instructions on the bottle. The most impressive part is its effectiveness. Since using this conditioner, I’ve noticed that my fish are visibly healthier and more active. Their colors are more vibrant, and they seem less stressed, especially after water changes or when introducing new fish to the tank. The product claims to reduce fish stress by 40% and it really seems to live up to that promise. Another major benefit is how it treats tap water. The conditioner neutralizes chlorine, chloramines, and heavy metals present in tap water, making it safer for the aquarium. This is crucial for the wellbeing of the fish and helps maintain a balanced ecosystem in the tank. Overall, I highly recommend the API STRESS COAT Aquarium Water Conditioner to any aquarium enthusiast. Whether you’re a beginner or an experienced fishkeeper, this product is a must-have in your aquarium care toolkit. It’s a small investment for the huge benefit it brings to the health and happiness of your aquatic pets. ... show more
Reviewed in the United States on January 18, 2024 by Tye
    • A must have
Size: 8 fl oz Style: Aquarium Treatment without Pump
Stress Coat is wonderful stuff. One of my Orandas was laying eggs and one of my males tore off a few of the scales on her side overnight. I put her in a hospital tank with Stress Coat and she was visibly better within a few days. And within a few hours after the move she had settled down and wasn't as agitated. Definitely something every aquarium owner should have on hand. ... show more
Reviewed in the United States on July 6, 2026 by Dianne
    • Super Value Of Great Product
Size: 16 fl oz Style: Aquarium Treatment without Pump
I've been using this stuff for years and I usually buy local but I saw the price , already had something in my cart so I added it to save me a trip to the pet big box store . I thought I was getting the usual small bottle and when it arrived and it was 16oz I immediately thought there was a mistake . I went back and looked and it was correct . I usually get 4oz for the same price (unless on sale) locally (big box per store) and I didn't have to fight mall traffic only to search forever for a parking spot . When starting a new setup , doing a partial water change , or just adding water this stuff is a must . I add 1 gallon at a time to my 50 gallon tank and the 1 gallon mark doesn't exist but I measured out the correct amount the first few times and now just approximate it using the cap to just about double what 1 gallon calls for . It works instantly , unlike some others , so I can do the needed addition at my convenience and the fish don't seem to mind the fresh water going into the tank . No color , no change in chemical and biological balances and no smell . If you've got a fresh water tank you need this stuff . ... show more
Reviewed in the United States on August 16, 2025 by Stephen Elmore
    • Nice product
Size: 16 fl oz Style: Aquarium Treatment without Pump
It looks to work well. I see some bubbles in the water surface after using this product, but it may not be a real issue.
Reviewed in the United States on February 28, 2026 by Cliente Kindle
    • Try it
Size: 128 fl oz Style: Aquarium Treatment without Pump
It helps with the plants that's easily to get their tits Brown it helps cut back on that and I like it.
Reviewed in the United States on August 12, 2026 by Auntbigg
    • Great water conditioner for your fish
Size: 16 fl oz Style: Aquarium Treatment without Pump
I use this all the time to kill the chlorine and make the water appropriate for my tank the tank stays clear and clean longer seemingly when I use it as well
Reviewed in the United States on August 25, 2026 by spanish1
    • It’s more than for aquariums!
Size: 1 fl oz Style: Aquarium Treatment without Pump
I started using this product in 2024 for my bamboo stalks that are in vases filled with tap water. My bamboos couldn’t be more happier and lovelier ever since! This 1 oz bottle is less than $3 and much cheaper than the similar products for houseplants. The water conditioner for houseplants can also be used for aquariums. So, why pay more when they do the same job? ... show more
Reviewed in the United States on July 24, 2026 by Mamacat

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