API Stress Coat Aquarium Water Conditioner, 64-fl oz bottle

$34.85 (-34%) Chewy Price
$52.78 List Price

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About This Item

Details

  • Helps reduce chlorine, chloramines and heavy metals that can harm your finned friend.
  • Fast-acting formula conditions tap water for use in freshwater aquariums.
  • Ideal for when starting an aquarium, adding a new fish, or during routine water changes.
  • Soothing aloe vera helps replace and protect your fish’s slime coat for added safety.
  • Delivers long-lasting protection to help keep your fish healthy.

Instructions

FAQ

Learn More About API From Our Team of Experts

Special Note
  • 1-oz bottle treats up to 60 gallons.
  • 8-oz bottle treats up to 470 gallons.
  • 16-oz bottle treats up to 940 gallons.
  • 64-oz bottle treats up to 3786 gallons.
  • 1-gal treats up to 7600 gallons.

About API Water Conditioners

It’s Smart To Be Proactive!

The best way to keep your aquarium clean is to maintain good water quality. This will help keep your fish strong and vibrant and prevent disease. Water conditioners and test kits from API can help you keep your aquarium water safe and healthy.

How Do I Maintain a Healthy Environment?

It is important to test your aquarium water weekly to ensure it stays healthy for your fish.  In addition, a bi-weekly partial water change of no more than 25% will help reduce toxic buildup, remove debris the filter missed, and replenish the oxygen available to your fish.

Feed Twice Daily and Test Water Weekly

Feed your fish twice a day, check their water temperature, and observe them to make sure they are active. You should also test water quality weekly for optimal safety. For fish to thrive, their water must closely match that of their natural environment—poor water quality can cause stress, illness and even fish loss. The 6 important parameters for healthy aquarium water are ammonia, nitrite, nitrate, pH and water hardness (GH & KH). All of these can vary over time and are invisible to the eye.

Change Water and Restore the Ecosystem

In a closed aquarium environment, there are no natural rivers or streams to carry away debris and other waste materials. That is why you should replace 25% of your aquarium water every two weeks, making sure to add water conditioner to your tap water to make it safe for your fish. You should also change your filter media and clean your gravel monthly. Adding beneficial nitrifying bacteria with API Quick Start when you do will help restore your aquarium’s fragile ecosystem and avoid disruption.

What Do API Products Do and When Do I Use Them?

API Test Kits

Use test kits weekly to monitor water quality parameters, which can vary over time and impact the health of your fish.

API Stress Zyme

Using this every week will help keep your aquarium clean and your gravel and ornaments sludge-free.

API Algaefix

Use weekly to control algae growth and keep aquarium glass, ornaments and plants clean.

API Stress Coat

Use every 2 weeks during water changes to make tap water safe, and when adding fish, or when fish are injured.

About API

The team at API has a passion for fish and understands the rewards and relaxation fishkeeping can bring. For almost 60 years, they have developed premium products with a focus on proven and effective results. API offers a range of testing kits, water conditioners and nutritionally superior fish foods. They are dedicated to making a better underwater world for the benefit of fish and those who keep them.

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Questions & Answers

37 Customer Questions


Is this ok for African dwarf frogs too? I have been using it in my community tank with the frogs in it along with the fish

Answer by ChewyAug 23, 2018
This product is not formulated for amphibians.

When using this product do i still have to use a regular water conditioner or do i use just this ans nothing else?

Answer by ChewyDec 22, 2018
This product removes chlorine and chloramines so no other conditioner is needed. Additionally, it detoxifies heavy metals, reduces fish stress and replaces the slime coat on your fish.

I am barely going to buy this after using a plain water conditioner. Would I have to do a complete water change with API stress coat in order to get the best results for the benefits it offers?

Answer by ChewyFeb 06, 2018
A complete water change would not be necessary if using this product as directed.

Do I use this every day like a typical betta water conditioner, or just after doing water changes?

Answer by ChewyFeb 19, 2018
The conditioner should be used when setting up an aquarium, adding or changing water, when adding a new fish, or when fish are damaged by injury or disease.

4.8
Rated 4.8 out of 5 stars
698 Ratings

205 Customer Reviews



Rated 5 out of 5 stars
By Debbie on Oct 22, 2025

Chewy Has What I Need

The person who took my order...Sherry was great. She did research, was real, had sense of humor, efficient. Order was accurate and received quickly. Thank you to

The person who took my order...Sherry was great. She did research, was real, had sense of humor, efficient. Order was accurate and received quickly. Thank you to everyone involved with order.


Rated 5 out of 5 stars
By Samantha on Nov 28, 2025

Will always recommend this

I always add this to my tank when adding fish or doing water changes. Hasn't failed me yet! Fantastic stuff!

I always add this to my tank when adding fish or doing water changes. Hasn't failed me yet! Fantastic stuff!


Rated 5 out of 5 stars
By Matt on Dec 24, 2025

I used to use Novaqua

I need to reduce the harmful chemicals when I make water changes in my aquariums

I need to reduce the harmful chemicals when I make water changes in my aquariums


Rated 5 out of 5 stars
By Robert on Dec 1, 2025

On time as always

Chewey makes my dog food shopping easy. It’s very convenient and easier on my back

Chewey makes my dog food shopping easy. It’s very convenient and easier on my back


Rated 5 out of 5 stars
By Stephen on Dec 22, 2025

I raise tropical fish this stresscoat does wonders

I have used this for all my fish from New ones to older ones.

I have used this for all my fish from New ones to older ones.


Rated 5 out of 5 stars
By June on Aug 6, 2025

10 Years of trust

I depend on this for my fish. I have used this for 10 years, possibly longer. Great for starting tanks, adding new fish or during water changes.

I depend on this for my fish. I have used this for 10 years, possibly longer. Great for starting tanks, adding new fish or during water changes.


Rated 5 out of 5 stars
By Aimee on Dec 15, 2025

Great product

Great product, great price, fast delivery

Great product, great price, fast delivery


Rated 5 out of 5 stars
By San on Dec 11, 2025

Good price and timely delivery

Great price and perfect delivery from chewy

Great price and perfect delivery from chewy


Rated 5 out of 5 stars
By Theresa on Oct 21, 2025

great deal

Good product, have been using for several years now.

Good product, have been using for several years now.


Rated 1 out of 5 stars
By Danielle on Jul 19, 2025

Not good

After 3 days my fish were gone and it did not help. Unfortunately buying this may kill your fish like it did for mine

After 3 days my fish were gone and it did not help. Unfortunately buying this may kill your fish like it did for mine