Safely and quickly lower the pH in your freshwater aquarium for more acidic water conditions with API's pH Down Aquarium Water Treatment. Different fish need different pH levels to stay healthy. For example, most freshwater fish thrive in levels between 6.5 and 7.5, but Cichlids and crustaceans require higher pH levels between 7.8 and 8.8. Levels that are too high, or too low, can cause stress, illness and even lead to loss, so testing is crucial to the health of your fish. API pH Down is designed to lower pH in water that tests at an undesirable level. It is fast-acting, colorless and easy to use. It should not cloud or color aquarium water, and because it's phosphate- and nitrate-free, it should not encourage algae growth.
Safely and quickly lower the pH in your freshwater aquarium for more acidic water conditions with API's pH Down Aquarium Water Treatment. Different fish need different pH levels to stay healthy. For example, most freshwater fish thrive in levels between 6.5 and 7.5, but Cichlids and crustaceans require higher pH levels between 7.8 and 8.8. Levels that are too high, or too low, can cause stress, illness and even lead to loss, so testing is crucial to the health of your fish. API pH Down is designed to lower pH in water that tests at an undesirable level. It is fast-acting, colorless and easy to use. It should not cloud or color aquarium water, and because it's phosphate- and nitrate-free, it should not encourage algae growth.
Safely and quickly lower the pH in your freshwater aquarium for more acidic water conditions with API's pH Down Aquarium Water Treatment. Different fish need different pH levels to stay healthy. For example, most freshwater fish thrive in levels between 6.5 and 7.5, but Cichlids and crustaceans require higher pH levels between 7.8 and 8.8. Levels that are too high, or too low, can cause stress, illness and even lead to loss, so testing is crucial to the health of your fish. API pH Down is designed to lower pH in water that tests at an undesirable level. It is fast-acting, colorless and easy to use. It should not cloud or color aquarium water, and because it's phosphate- and nitrate-free, it should not encourage algae growth.
Safely and quickly lower the pH in your freshwater aquarium for more acidic water conditions with API's pH Down Aquarium Water Treatment. Different fish need different pH levels to stay healthy. For example, most freshwater fish thrive in levels between 6.5 and 7.5, but Cichlids and crustaceans require higher pH levels between 7.8 and 8.8. Levels that are too high, or too low, can cause stress, illness and even lead to loss, so testing is crucial to the health of your fish. API pH Down is designed to lower pH in water that tests at an undesirable level. It is fast-acting, colorless and easy to use. It should not cloud or color aquarium water, and because it's phosphate- and nitrate-free, it should not encourage algae growth.
Last updated at 05/30/2026 19:35:17
API pH DOWN Freshwater Aquarium Water pH Reducing Solution 16-Ounce Bottle
Free delivery
Affiliate Disclosure: We may receive a small commission for purchases made through this link at no extra cost to you. This helps support our site. Thank you!
API P.H. Down 473ml
API, pH Down Aquarium pH Adjuster, 16 oz
Delivery $26.50
API PH Down Freshwater Aquarium Water Treatment 473ml
Delivery between 3–9 June $8.61
API Ph Down 473ml
Api P H Down
Delivery between 6–9 June $29
API pH Down 473ml
Delivery $9.50
API pH Down 473mL
API pH Down Liquid - AquaticSupplies.com.au 473ml
Delivery between 4–9 June $11.95
API PH Down 473ml
Free delivery by Tue
| Product dimensions | 6.35 x 6.35 x 22.23 cm; 544.31 Grams |
| Country of origin | USA |
| Is discontinued by manufacturer | No |
| Liquid volume | 16 Fluid Ounces |
| Item form | Liquid |
API pH DOWN Freshwater Aquarium Water pH Reducing Solution 16-Ounce Bottle
Free delivery
Affiliate Disclosure: We may receive a small commission for purchases made through this link at no extra cost to you. This helps support our site. Thank you!
API P.H. Down 473ml
API, pH Down Aquarium pH Adjuster, 16 oz
Delivery $26.50
API PH Down Freshwater Aquarium Water Treatment 473ml
Delivery between 3–9 June $8.61
API Ph Down 473ml
| Product dimensions | 6.35 x 6.35 x 22.23 cm; 544.31 Grams |
| Country of origin | USA |
| Is discontinued by manufacturer | No |
| Liquid volume | 16 Fluid Ounces |
| Item form | Liquid |
