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API

API STRESS COAT Aquarium Water Conditioner 16-Ounce Bottle

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Availability: In Stock.
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Arrives Thursday, Dec 18
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Size: 16 fl oz


Style: Aquarium Treatment


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


Manufacturer: Mars Fishcare


Is Discontinued By Manufacturer ‏ : ‎ Yes


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


Item model number ‏ : ‎ 85C


Department ‏ : ‎ Unisex-Adult


Date First Available ‏ : ‎ June 15, 2004


Manufacturer ‏ : ‎ Mars Fishcare


Best Sellers Rank: #1,072 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 (37,681)


Item Weight: 6.4 ounces


Department: Unisex-Adult


Manufacturer: Mars Fishcare


Item model number: 85C


Date First Available: June 15, 2004


Item Package Dimensions L x W x H: 8.46 x 2.29 x 2.24 inches


Item Dimensions LxWxH: 5 x 1 x 5 inches


Brand Name: API


Target Audience Keyword: fish


Directions: Use when setting up an aquarium, adding or changing water, when adding new fish, or when fish are damaged by injury or disease. Using dosing cap on bottle, add 5 ml per 10 gallons of aquarium water. Double the dose to replace slime coat and to repair damaged skin and fins. Use STRESS COAT together with API STRESS ZYME to assure good water quality and a healthy, clean aquatic environment.


Country of Origin: United States


Model Name: STRESS COAT, 16 OZ


Color: Multi-colored


Size: 16 fl oz


Material: Plastic


Number of Items: 1


Style: Aquarium Treatment


Breed Recommendation: All Breed Sizes


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Dec 18

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

    • 5/5 Great for my fish
Size: 16 fl oz Style: Aquarium Treatment
5/5 – Great for Fish Health and Clear Water I’ve been using API Stress Coat for years, and it’s one of my must-have aquarium products. It instantly removes chlorine and chloramines from tap water, making it safe for fish right away. I especially like that it contains aloe vera, which helps reduce fish stress and promotes healing of minor scrapes or torn fins. The 16-ounce bottle lasts a long time — just a small amount treats many gallons. I use it during water changes and whenever I introduce new fish, and I’ve noticed my fish stay calmer and healthier. It doesn’t cloud the water, and I’ve never had any issues with it affecting my filtration or plants. The cap makes dosing easy, and the directions are clear. If you want a water conditioner that also supports fish health, this is a solid choice. Highly recommend for both beginner and experienced aquarium keepers. ... show more
Reviewed in the United States on August 12, 2025 by J Harris
    • Super Value Of Great Product
Size: 16 fl oz Style: Aquarium Treatment
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
    • Magic in a Bottle for Your Aquarium!
Size: 16 fl oz Style: Aquarium Treatment
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
    • All API products are good. Stress Coat is a miracle medicine.
Size: 16 fl oz Style: Aquarium Treatment
I add API Stress Coat to all new water before it goes into my aquarium. I also add a enough hot water to make it the same temperature as the aquarium. Add an extra dose when add fish. Add an extra dose whenever fish appear ill or stressed. It truly is an first-resort, miracle medicine for fish. THE FOLLOWING REVIEWS ARE FOR ALL OF MY AQUATIC PURCHASES. I always read two dozen or more User Reviews for any product I buy. Amazon is honest and prints both the good and the bad reviews. I bought the following products from Amazon: >*****> Hagen Marina Ecoscaper Hydrocotyle Silk Plant. I am really pleased with this plant. And the fish like it too . . . no rough edges. It is just as pictured and looks so realistic. >*****> Hagen Exo Terra Water PLANT, Duckweed. It looks and floats just like real duckweed ! I showed it to the aquatics people at Petco and they were impressed. >*****> Hydor Theo Submersible Aquarium HEATER 25W UL. Very small and easy to adjust; plus it can be placed completely underwater in any position: vertical, horizontal, or on an angle. >*****> Hagen Elite Underwater Mini FILTER for up to 3 gallon tank. >*****> Hagen Elite Mini Internal FOAM 5 PACK replacement sponges. This is an excellent filter for my 5 gallon tank. It is well-made and powerful and could filter a 10 gallon tank. To reduce the water current to make it easy on my fish, I TOOK THE ADVICE FROM A USER REVIEW and bought a 5-pack of replacement sponge filters and used one sponge to completely cover the outflow valve. I also put a wee bit of the foam filter in the Venturi diffuser aerator. I set the aerator to low, which still provides ample aeration. I set the green filter power dial on the side of the filter to low to be just enough to create a good supply of aerating bubbles. I operated the aquarium for over a month without fish so that the water would be biologically perfect for them. Petco checks water samples for free. That little $9 dollar bio filter is just a wonder and so easy to maintain. Unplug the filter and remove it from the aquarium, then syphon off some aquarium water ( never use tap water) and squeeze the foam sponge in clean aquarium water three times or more until the final wash water is almost clear, then replace the sponge in the filter. I now have 5 Von Rio "Flame" Tetras doing very well in their new home. They do best when in a group of 5 or more, and in a low light environment, so I must have low-light live plants. I have a well-planted 5 gallon corner-type aquarium with a lid just for these 5 beautiful and hardy little orange fish. To provide shelter, there are lots of live Java ferns and wisteria plants at each end, plus the hydrocotyle silk plant to hide the filter and heater, and the plastic floating duckweed to provide shelter from above. I purchased the silk hydrocotyle and plastic duckweed, because these live plants would perish in low light. Fish, like all living creatures, need shelter from real or perceived threats. Stress is the cause of most of life's mental and physical illnesses. For many years, I have purchased almost every type of product from Amazon and never had a problem. Products are as advertised, or better, and Super Saver Shipping is fast and dependable. I recommended all of the above products to my friends. I tell everyone to save money and buy through Amazon ( including the aquatics people at Petco ). // ... show more
Reviewed in the United States on December 15, 2012 by Miss Paula from South Beach, Miami, Florida
    • For my house plants
Size: 16 fl oz Style: Aquarium Treatment
I add just a little bit to my house water for my houseplants weekly. Plus I use in our fish tank. Double use. Very easy to use and pleased with the outcome.
Reviewed in the United States on October 10, 2025 by Susan Wiles
    • Great for plants too!
Size: 16 fl oz Style: Aquarium Treatment
This is a great product for plant care too! Just a couple of drops in your watering can and it conditions the water and neutralizes chemicals fussy plants don't like, like Marantas turning their leaves crispy brown.
Reviewed in the United States on November 12, 2025 by AnitaPK
    • Great for the amount you receive. Worth it
Size: 16 fl oz Style: Aquarium Treatment
The amount you get is so worth it. A small bottle where I live is 4.99. This is great
Reviewed in the United States on November 3, 2025 by S. R. Martinez

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