API Tap Water Conditioner, 16-fl oz bottle

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About This Item

Details

  • Helps to remove chlorine, chloramines and detoxifies heavy metals.
  • Super concentrated, so you will only need one 1 ml to treat gallons.
  • Safe for all aquatic and can be used in both fresh and salt water.
  • Use during aquarium set up, water changes and adding fish.
  • Tap water must be treated before adding fish to make sure they remain healthy.

Instructions

FAQ

Learn More About API From Our Team of Experts
Special Note
  • 8-oz bottle treats up to 4730 gallons.
  • 16-oz bottle treats up to 9460 gallons.
  • 1-gal treats up to 76000 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

27 Customer Questions

I purchased API Quick Start...do I still need to use this tap water conditioner along with Quick Start or just one is needed?

Answer by Chewy • Oct 09, 2018
Quick Start should be added to dechlorinated water, otherwise the chlorine can harm the beneficial bacteria it contains, as well as the fish you are trying to keep. It is recommended to treat the water first with API Tap Water Conditioner before adding new water to the tank, to remove the chlorine and chloramines. The Quick Start would then be added directly to the aquarium. Quick Start contains only the live bacteria -- it does not contain a dechlorinator, so both are necessary for a happy and healthy aquarium.

How long do you have to wait to put the fish back in after using the water conditioner?

Answer by Chewy • May 10, 2019
The API Tap Water Conditioner removes toxins instantly, so you can add fish to your aquarium (or add them back after a water change) immediately.

Do I need to remove my turtle before using API Tap Water Conditioner?

Answer by Chewy • Jun 19, 2020
This conditioner is made to use for tanks with fish and should not be used with turtles.

Can i add the tap water conditioner in whilst my fish are in tank

Answer by Chewy • Jul 09, 2021
This water conditioner is designed for use when setting up a new aquarium, and when adding or changing water. Fish do not need to be removed from the tank.
Reviews
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4.8
Rated 4.8 out of 5 stars
448 Ratings
Terms & Conditions

119 Customer Reviews

Rated 5 out of 5 stars
By MONICA on Oct 30, 2025

Quick delivery

Needed maintenance on my aquarium and ordered items I needed without having to drive around to different pet stores, since not all have everything I needed.

Needed maintenance on my aquarium and ordered items I needed without having to drive around to different pet stores, since not all have everything I needed.

Rated 5 out of 5 stars
By John on Oct 28, 2025

Highly Recommended

Great product. A small amount goes a long way (5 mil per 50 gals). No issues with our Koi or Goldfish

Great product. A small amount goes a long way (5 mil per 50 gals). No issues with our Koi or Goldfish

Rated 4 out of 5 stars
By Nicole on Sep 1, 2025

It Does the job

I mean who really knows, the other popular brand has a strong scent. This one doesn't but as long as it gets the bad stuff out who cares

I mean who really knows, the other popular brand has a strong scent. This one doesn't but as long as it gets the bad stuff out who cares

Rated 5 out of 5 stars
By Goldie on Sep 20, 2025

Pond treatment

Best highly concentrated pond treatment to remove chlorine from my backyard pond.

Best highly concentrated pond treatment to remove chlorine from my backyard pond.

Rated 5 out of 5 stars
By Anastasia on May 29, 2025

Doubles down as a houseplant water conditioner!

I use it to remove chlorine before I water my plants, including sensitive calatheas. A little goes a long way, so the bottle lasts. Great hack

I use it to remove chlorine before I water my plants, including sensitive calatheas. A little goes a long way, so the bottle lasts. Great hack

Rated 5 out of 5 stars
By Kasi on May 11, 2025

Must have

We use tap water to make sure the water goes in warm so this product is a must have. We have never had an issue using it with our turtle.

We use tap water to make sure the water goes in warm so this product is a must have. We have never had an issue using it with our turtle.

Rated 4 out of 5 stars
By Anne on Aug 20, 2025

My cat treats were damaged

Every order of cat treats is cracked open. Not cool

Every order of cat treats is cracked open. Not cool

Rated 5 out of 5 stars
By Naja on May 29, 2025

Works Fast

Highly concentrated so you don’t need a lot. Works instantly. My go to tap water conditioner.

Highly concentrated so you don’t need a lot. Works instantly. My go to tap water conditioner.

Rated 5 out of 5 stars
By Joe on Oct 14, 2025

My fish

I used it for my fish tank

I used it for my fish tank

Rated 5 out of 5 stars
By ft25 on Jan 1, 2025

Sodium thiosulfate and thats it

This is all you need--the other "stress" products are more harmful than helpful, adding unnecessary chemicals that actually foul water longer term, especially if

This is all you need--the other "stress" products are more harmful than helpful, adding unnecessary chemicals that actually foul water longer term, especially if you need to overdose when the water company shocks the system with chlorine. You want to use a straight up sodium thiosulfate dechlorinator at many times the dose for every water change because when (not if) your water supplier shocks the delivery system, you may kill fish due to the additional chlorine. This is because chloramine is only effective as a disinfectant for a while, before it can't penetrate biofilms. So the water suppliers will sometimes shock delivery systems to flush the films. It explains many unexplained fish deaths. Beware!