API Proper pH 6.5 Freshwater Stabilizer

Why this product matters

Getting the right pH for your freshwater fish isn't just chemistry—it's the foundation of a thriving aquarium. This stabilizer automatically sets and maintains pH at 6.5, the sweet spot for tetras, discus, rasboras, and angelfish while removing harmful tap water chemicals. Keep reading for all the details.

Product Description

This 8.5 oz (251 ml) pH stabilizer does double duty in your freshwater tank. It automatically adjusts and locks your water pH to 6.5, which is ideal for many popular tropical fish species. But it goes beyond just pH—it also neutralizes chlorine, removes chloramines, detoxifies heavy metals, and adds beneficial electrolytes to make tap water safe for your fish.

Use it when setting up new tanks, during water changes, or whenever you need to adjust pH levels. Since aquarium pH can fluctuate due to fish waste, leftover food, and fresh tap water additions, weekly testing is recommended to maintain stable conditions.

Interesting Points

Perfect pH for Popular Fish

The 6.5 pH level this product maintains is specifically chosen for tetras, discus, rasboras, and angelfish—some of the most beloved freshwater species that thrive in slightly acidic conditions.

Multiple Water Treatment Benefits

Beyond pH control, this formula removes toxic chlorine compounds, neutralizes chloramines, detoxifies heavy metals, and adds essential electrolytes in one treatment.

Automatic Stabilization

Unlike manual pH adjusters, this product automatically sets and maintains the target pH, reducing guesswork and providing consistent water conditions for your fish.

Trusted Brand Heritage

Made by API, a company with over 50 years of aquarium care innovation, ensuring you're using research-driven solutions for your tank.

Product Specifications

• Container size: 8.5 oz (251 ml)
• Target pH level: 6.5
• Suitable for: Freshwater aquariums
• Ideal fish species: Tetras, Discus, Rasboras, Angelfish
• Additional functions: Chlorine removal, chloramine neutralization, heavy metal detoxification
• Brand: API

Usage Notes

• Test water pH weekly for best results
• Use when setting up new aquariums
• Apply during water changes
• Follow all product directions for optimal results
• Works best when used with other API aquarium products

Package Inclusion

• 1 bottle API Proper pH 6.5 Freshwater Stabilizer (8.5 oz)

Create the perfect environment for your tetras, discus, and other acid-loving fish with this professional-grade pH stabilizer that does more than just adjust—it protects and maintains optimal water conditions automatically.

Shipping and Returns

• Listed Shipping: 2–4 days.
• Returns: Returns policy.