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API STRESS COAT Aquarium Water Conditioner 5-Gallon Bottle

  • Based on 38,563 reviews
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Size: 640 fl oz


Style: Aquarium Treatment without Pump


Features

  • Contains one (1) API STRESS COAT Aquarium Water Conditioner 5-Gallon 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, shipping 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

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: 5 gallons


Item Weight: 16 ounces


Item Form: Liquid


Unit Count: 640 Fluid Ounces


Product Dimensions ‏ : ‎ 1 x 1 x 1 inches; 1 pounds


Item model number ‏ : ‎ 85E


Date First Available ‏ : ‎ October 2, 2001


Manufacturer ‏ : ‎ Mars Fishcare


Best Sellers Rank: #857 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 (38,563)


Brand Name: API


Unit Count: 640 Fluid Ounces


Manufacturer: Mars Fishcare


UPC: 317163140857


Global Trade Identification Number: 57


Item Type Name: Aquarium Water Conditioner


Model Number: 85E


Manufacturer Part Number: 85E


Liquid Volume: 5 gallons


Item Weight: 16 ounces


Item Form: Liquid


Pet Type: Fish


Target Species: Fish


Allergen Information: Apple Free


Frequently asked questions

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Similar Products

Top Amazon Reviews

    • All API products are good. Stress Coat is a miracle medicine.
Size: 16 fl oz Style: Aquarium Treatment without Pump
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
    • 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
    • Wonderful water conditioner!!! :)
Size: 16 fl oz Style: Aquarium Treatment without Pump
For use in aquariums and plant water to remove chlorine and chloramine and it does a wonderful job!
Reviewed in the United States on June 11, 2026 by Jennifer
    • Excellent for keeping fish healthy
Size: 16 fl oz Style: Aquarium Treatment without Pump
I depend on the API Stress Coat to keep my fish healthy and happy! It is convenient to use and lasts a long time. It does a great job at helping keep nitrates low, keeps water clear and is safe and effective to use.
Reviewed in the United States on June 8, 2026 by Rand
    • 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
    • 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
    • Should be a requirement for any hobbyist
Size: 16 fl oz Style: Aquarium Treatment without Pump
Excellent product. No odors. Cap comes with measuring lines. Works instantly. I buy this on repeat anytime I get low.
Reviewed in the United States on June 25, 2026 by Kmlo
    • Works Great
Size: 128 fl oz Style: Aquarium Treatment without Pump
Review Image by Emilyah
I keep guppies and this works to keep the water safe for them. Two thumbs up 👍 👍
Reviewed in the United States on July 28, 2026 by Emilyah

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