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API pH Down, Freshwater Aquarium Water pH Reducing Solution, 1.25 oz
Key item features
Contains one (1) API pH DOWN Freshwater Aquarium Water pH Reducing Solution 1.25-Ounce Bottle,Lowers freshwater aquarium water pH with a phosphate-free formula,Does not promote algae growth with pH adjustments and is safe for plants and fish,Slowly neutralizes alkaline substances that cause high water pH,Test water weekly and use to correct pH level in freshwater aquariums
Specs
- Aquarium water treatment typeAquarium Water Conditioner
- BrandAPI
- Size16 oz
- Pack quantity1
- Animal typeAll Pets
- FeaturesSafe
Current price is USD$9.69
Price when purchased online
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Columbus, 43215
Arrives between May 11 - May 13
|Sold and shipped by Kwik Retail
4.496082187010273 stars out of 5, based on 5749 seller reviews(4.5)5749 seller reviews
Free 30-day returns
About this item
Product details
pH is the measure of acidity of water, on a scale ranging from 0 to 14. A pH of 0 is the most acidic, while a pH of 14 is the most alkaline. Different geographies have different tap water conditions with different pH levels, while fish require a specific pH level to thrive. A pH of 7.0 is ideal when keeping a community aquarium containing a variety of tropical fish. Goldfish and livebearers prefer a pH of 7.5. Many Amazonian fish, like angelfish and neon tetras, prefer a pH of 6.5 to 6.8. Mollies and swordtails thrive at pH 7.2 to 7.5. API pH DOWN Freshwater Aquarium Water pH Reducing Solution lowers aquarium pH in freshwater aquariums to desired level. Safe for fish and plants. Use when setting up a new aquarium, adjusting pH, or changing water. pH in an aquarium can fluctuate due to fish waste, uneaten food and addition of tap water. It is recommended to test water for pH weekly. With API Aquarium products, it’s easy to keep a beautiful saltwater, freshwater or reef aquarium. For over 50 years, API has been creating innovative, research-driven solutions that make it easier to care for your fish and aquarium. API Aquarium Treatment Supplies are designed to work in conjunction with each other to provide best results to control algae, promote healthy bacterial growth and help control and fish diseases and conditions such as ich and fin rot. They work to provide a safe, hospitable environment for fish such as tropical community fish, cichlids, goldfish and more. With API, you can spend more time admiring your fish, and less time scrubbing your tank. Make sure to use all products as directed in order to ensure the best results.
Contains one (1) API pH DOWN Freshwater Aquarium Water pH Reducing Solution 1.25-Ounce Bottle,Lowers freshwater aquarium water pH with a phosphate-free formula,Does not promote algae growth with pH adjustments and is safe for plants and fish,Slowly neutralizes alkaline substances that cause high water pH,Test water weekly and use to correct pH level in freshwater aquariums
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Specifications
Aquarium water treatment type
Aquarium Water Conditioner
Brand
API
Instructions
Use when setting up a new aquarium, adjusting pH, or changing water. It is recommended to test water for pH weekly.
Size
16 oz
Directions
Instructions
Use when setting up a new aquarium, adjusting pH, or changing water. It is recommended to test water for pH weekly.
Warranty
Warranty information
All products come with a 90 Day, or longer, manufacturer warranty
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Please be aware that the warranty terms on items offered for sale by third party Marketplace sellers may differ from those displayed in this section (if any). To confirm warranty terms on an item offered for sale by a third party Marketplace seller, please use the 'Contact seller' feature on the third party Marketplace seller's information page and request the item's warranty terms prior to purchase.
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Customer ratings & reviews
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Showing 1-3 of 3 reviews
Oct 22, 2025
charles
Top Reviewer
Item details
Sold and shipped byLittle Family MembersSize: 16 oz
5 out of 5 stars review
Verified Purchase
Bye Bye algae
This product API pH Down is excellent for my 35-gallon and my 75-gallon Aquariums. My tanks are fairly close to windows, with a steady maintenance each 3 to 4 weeks. One of my dislikes was two drops per gallon, there's room for error.
Incentivized Review
Helpful?24NFKX7K5K7724918076
Nov 6, 2025
Rick21550
Item details
Sold and shipped byKwik RetailSize: 16 oz
5 out of 5 stars review
Verified Purchase
Does exactly what it's supposed to
Incentivized Review
Helpful?24NFKX7K5K7724918076
Aug 2, 2023
Cristina
Item details
Sold byJosh's FrogsSize: 16 oz
5 out of 5 stars review
Verified Purchase
Good product
Works as described no issues
Incentivized Review
Helpful?24NFKX7K5K7724918076

