API pH Up Freshwater Aquarium Water Treatment

Rated 4.4 out of 5 stars


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$18.58Chewy Price
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About This Item


  • Safely raises pH in freshwater aquariums to desirable levels.
  • Fast-acting, concentrated, colorless and easy to use.
  • Phosphate- and nitrate-free, so it should not encourage algae growth.
  • Formulated to not cloud or cause water discoloration.
  • Helps keep your freshwater aquarium water in tip-top condition for your finned friends.

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Play Video: Learn More About API From Our Team of Experts
Learn More About API From Our Team of Experts

Help keep your saltwater aquarium in tip-top shape with API's Marine Master Test Kit or Saltwater Master Test Kit.
Test your freshwater or saltwater aquarium's water with API's 5 in 1 Test Strips.
Measure your freshwater aquarium's pH level with API's Freshwater Master Test Kit.
Test your aquarium's pH level with API's pH Test Kit, pH Test and Adjuster Kit or pH Test Strips.

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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Fish TypeBetta, Bottom Feeder, Cichlid, Goldfish, Tropical FreshwaterBetta, Bottom Feeder, Cichlid, Goldfish, Tropical FreshwaterMarine Fish, Tropical FreshwaterTropical FreshwaterKoi & Pond Fish
Aquarium TypeFreshwaterFreshwaterSaltwater, FreshwaterFreshwaterPond

Questions & Answers

9 Customer Questions

Does this product also increase kh?
Answer by ChewyMay 27, 2022
This treatment raises KH.

I have a back yard pond and also a large fish tank holding a red eared slider in it, in my garage. Can you tell me the difference between PH UP for a pond and for a tank? Are they interchangeable??
Answer by ChewyFeb 09, 2022
API pH Up and API Pond pH Up can be used interchangably.

I read that API Proper PH should not be used in a planted Aquarium, is pH Up safe to use with plants?
Answer by ChewySep 17, 2019
API pH Up and API pH Down are safe for live plants.

Can I use this safely in a tank of fish that I intend to eat?
Answer by ChewySep 14, 2022
API products are intended for ornamental fish aquariums only. These are not appropriate for agricultural / food-fish use. We recommend only using products intended for agricultural use if you will be consuming your fish.

ReviewsWrite a Review

Rated 4.4 out of 5 stars
10 Ratings
Would recommend to a friend

10 Customer Reviews

Rated 1 out of 5 stars
By CS on Jun 25, 2023

Didn't work for us

I use a lot of API products to keep my turtle tank healthy, but for whatever reason, this product never once worked at raising the pH of my tank. I followed the instructions on the bottle and probably used about half the bottle in total, but never once did this increase my tank's pH. Just doing a water change works better, don't waste your money.

Rated 5 out of 5 stars
By Jay on May 7, 2023

Works as intended

Product does exactly what it's suppose to. API water treatments have been effective and affordable

Rated 5 out of 5 stars
By Lucy on Nov 29, 2022

PH up bottle

Perfect for raising PH Perfect amount Perfect price Perfect service

Rated 5 out of 5 stars
By Angel on Nov 11, 2021

Works as intended

Helps to make sure my cichlids are comfortable. Works as promised, better than the powdered versions.

Rated 5 out of 5 stars
By laurie on Feb 16, 2021

test your ph first

I spent so much money trying to figure out why green slime kept growing and fish were dying and all I needed to do was to test my tank and balance the PH no more algee and fish are happy

Rated 3 out of 5 stars
By bobo on Jul 11, 2020

ph up bottles

got ph up bottles deliverd to my house they were leaking in box need new ones

Rated 5 out of 5 stars
By Tamm on Jan 27, 2019

Great product

Fast shipper good product my fish love this stuff and so do i. Keep up the good work chewy.com

Rated 5 out of 5 stars
By Ferdie4 on Aug 13, 2018

More good product for the money

I usually get a small bottle of this for the same price. This will last much longer and helps keep the PH up in my tank. Even with frequent water changes & cleanings the PH needs help.

Rated 5 out of 5 stars
By Catfish143 on Dec 14, 2017

Good Stuff

This stuff really works. Be careful, read and follow directions. Don’t over do it. Raise the pH slowly for your finishes benefit. But API’s “pH UP”” will do it.

Rated 5 out of 5 stars
By 01Sunnygirl on Sep 6, 2017

Works good.

Ph up works really well for my cichlid tank. Chewy has the best price that I've found and the customer service is great!