API Marine Stress Zyme Saltwater Aquarium Cleaning Solution, 16-fl oz bottle

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About This Item

Details

  • Cleans live rock and sand while improving water quality, reducing maintenance and removing unwanted organics.
  • All-natural formula adds live beneficial bacteria to your aquarium and helps remove sludge.
  • Breaks down organic compounds that cause dangerous conditions such as ammonia, nitrate poisoning, and low oxygen levels.
  • Ideal for new saltwater or marine tanks, or when adding or handling fish.
  • Aquariums with less sludge are typically healthier and have more efficient biological filtration.

Instructions

FAQ

Learn More About API From Our Team of Experts

Special Note

16-oz bottle treats up to 948 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

2 Customer Questions


what's the difference between stress zyme saltwater and stress zyme fresh water and saltwater

Answer by ChewyAug 27, 2020
API Marine Stress Zyme Saltwater Aquarium Cleaning Solution is for saltwater use only. API Stress Zyme Freshwater & Saltwater Aquarium Water Cleaner is suitable for freshwater and saltwater.

can this be used in a freshwater tank?

Answer by ChewyFeb 06, 2019
This solution is formulated for use in saltwater and marine tanks.
4.8
Rated 4.8 out of 5 stars
20 Ratings

3 Customer Reviews



Rated 5 out of 5 stars
By Christine on May 6, 2025

The best for each water change

Fish are very healthy! Use it every week with the new water.

Fish are very healthy! Use it every week with the new water.


Rated 5 out of 5 stars
By Carolyn on Aug 27, 2025

Quality

Works well

Works well


Rated 5 out of 5 stars
By StephenS on Mar 9, 2024

I THINK IT HELPS!

I began using this product for freshwater tropical fish about 3 weeks ago. It seems to me that my new and old fish have an easier time adjusting to their water

I began using this product for freshwater tropical fish about 3 weeks ago. It seems to me that my new and old fish have an easier time adjusting to their water. I used extra doses for new fish and water changes. I won't guarantee it but I think that it helps.