Aquarium Pharmaceuticals® API pH Down 16oz
Lowers pH and makes aquariums more acidic. Fast-acting, colorless and easy-to-use.
Purpose and Benefits:
Directions for Use:
- pH Down is a liquid pH lowering product for freshwater aquariums. pH Down lowers pH by neutralizing carbonate hardness in the water.
- Adjusting the pH to the proper level will improve fish health, disease resistance, coloration and breeding. While many common aquarium fish will live in water with a pH range of 6.8 to 7.5, a pH of 7.0 is ideal for a community aquarium containing a variety of freshwater fish. Live bearers like mollies and swordtails prefer a higher pH of 7.2-7.6. Acid-loving fish such as angelfish and neon tetras prefer a lower pH of 6.5-6.8.
- Each dose of pH Down neutralizes some of the carbonate hardness and lowers the pH. The pH may rebound up to the original pH if the carbonate hardness is high. Several consecutive treatments with pH Down may be necessary to lower pH, but if there are fish present in the aquarium, the pH should not be changed more than .2 in a 24 hour period. The number of doses required to lower the pH will depend on the carbonate hardness level and the desired pH level. An aquarium with low carbonate hardness may require one treatment with pH Down while an aquarium with a high carbonate level will require several.
Compatibility: pH Down contains no phosphates and may be used with live plants.
- Use Aquarium Pharmaceuticals Freshwater pH test Kit to determine the pH of the aquarium.
- To lower pH, add two drops of pH Down for every U.S. gallon (3.78 L) of aquarium water.
- Take another pH reading before making the next addition of pH Down.
- If fish are present in the aquarium, do not change the pH more than 0.2 in a 24 hour period (for example, from 7.2 to 7.0).
How much pH Down will it take to lower my pH?
The amount of pH Down required to lower the pH of aquarium water depends on several factors. The primary cause of high pH is an elevated carbonate hardness (KH) level. Carbonate hardness, also known as alkalinity, is found in tap water and may also leach from aquarium gravel, ornamental shells, and coral. Each dose of pH Down neutralizes some of the carbonate hardness. It may take several doses of pH Down to neutralize enough carbonate hardness to lower the pH.
Why does my pH level drop after adding pH Down then bounce back up the next day?
pH rebound occurs when the carbonate hardness is high. Aquarium water with high carbonate hardness resists pH change.
Does pH Down contain phosphates?
No. pH Down contains no phosphoric acid or phosphates.
Can I add more than the recommended dose of pH Down?
Always follow the directions when using pH Down in the aquarium. Many aquarists treat a separate bucket of water with pH Down to adjust the pH before adding the water to the aquarium. Add as much pH Down to the bucket as necessary to lower the pH to the desired level. Once the pH has stabilized (12-24 hours), add the water to the aquarium.
Can I use pH Down in a saltwater aquarium?
Marine salts are formulated with a large amount of carbonate buffer to stabilize the pH. Each brand has its own unique formula and pH range. While adding pH Down to a saltwater aquarium is not harmful, it should not be used to adjust pH. Use Proper pH 8.2 to adjust and stabilize pH in saltwater aquariums.
Aquarium Pharmaceuticals Aquarium Supplies
Aquarium Pharmaceuticals (API) has been helping people take good care of ornamental fish for over 40 years. Their research and development scientists have advanced the care of fish with all-natural medications, stable bacteria for biological filtration, one-bottle test kits, consumer-friendly dosing caps and much more. They’ve received over 25 global patents for their breakthrough innovations in the aquatics industry. And they continue to look for ways to improve the fishkeeping experience for hobbyists. Research. Experience. Dedication to scientific, quality treatment for healthy fish. It’s what makes API the first choice of aquarium owners. API manufactures and sells hundreds of products across many different product categories, including aquarium and pond treatments, aquarium equipment, aquariums and fish nutrition.