Brightwell Aquatics

Florin pH- for Freshwater, Planted, & Marine Tanks (500 mL)

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$10.44 $12.28

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Decreases pH in all Freshwater, Planted, & Marine Aquariums

  • Safely decreases pH 
  • Gradually decreases alkalinity ("carbonate hardness") of tap water and aquarium water
  • Useful for establishing acidic water conditions for biotopes or encouraging spawning
  • Free of phosphates and nitrates
  • USP-grade ingredients


Many freshwater fish and moving invertebrates need the pH of the aquarium water to be below 7.0 (acidic) due to their natural habitat in forested areas with low mineral content. Aquarists face a challenge when trying to adjust the pH to the right level, especially when the water used for water changes has high mineral levels, or when using reactive aquarium substrate like dolomite or calcite. The first step is to use purified water mixed with a suitable remineralizing salt for water changes. It's important to use non-reactive substrate. Even with these changes, the pH may still be too high. Florin pH- can be used to gradually and safely decrease the pH as directed.


pH changes should always be made slowly to avoid stressing the aquarium inhabitants. It's important to consult a reliable source for the water chemistry requirements of the inhabitants before adjusting the pH. Alkalinity should also be monitored and adjusted if needed. Florin pH- is safe for all freshwater aquariums, including those with plants and moving freshwater invertebrates like shrimp, crustaceans, snails, and mollusks.


Instructions & Guidelines

Do not add Florin pH- to an aquarium without first determining pH and alkalinity with an accurate meter or test kit. Shake bottle before each use. Read entire instructions before proceeding.


Aquarium addition: Add up to 1 ml Florin pH- per 10 US-gallons (37.9 L) in system every two hours until pH has decreased and stabilized at or near the desired level; note that the rate of water circulation in the aquarium will impact the speed with which the active ingredients alter the pH of the system (faster circulation will decrease the time required for pH to change), and that pH stabilization may take up to 24 hours in extreme cases (it is far more likely to stabilize in less than 2 hours, however). Do not enact changes in pH of greater than 0.1 per 30 minutes. As Florin pH- is added to the system, alkalinity will decrease, causing pH to become less-stable and eventually decrease, also. In alkaline water conditions, it is common for pH to decrease temporarily and then increase slightly following addition of Florin pH-; this is simply due to interaction between the active components and the buffering molecules present in the water, and will gradually lessen as alkalinity decreases. At that point, pH will change easily with addition of Florin pH-, therefore proper caution should be exercised to ensure that pH does not drop below a safe level. Consult a reputable reference for alkalinity and pH requirements of the organisms being housed in the aquarium and make adjustments to these parameters as necessary to attain the desired values. Alkalinity may be increased through the use of a buffer (such as Brightwell Aquatics Florin Delta KH+); this will stabilize, and potentially slightly increase, pH.

Tap and/or purified water addition: Adjust alkalinity of water to desired value with a buffer (such as Brightwell Aquatics Florin Delta KH+); once alkalinity has stabilized, add Florin pH- until desired pH is attained. Finally, adjust TDS of water (such as with Brightwell Aquatics Remineralīz or Remineralīz-P, or with Florin Delta GH+ for planted aquaria) to desired value. When water temperature is approximately equivalent to that of aquarium water, add water to the aquarium.

Caution: Contains buffered sulfuric acid; contents may be corrosive and/or irritating. Do not breathe fumes. Keep out of reach of children. Not for human consumption. First Aid: If swallowed: rinse mouth, give water or milk. Do not induce vomiting. In the event of eye or skin contact, flush with water for at least 15 minutes. Contact a physician immediately.


Ingredients: USP-grade Sulfate salts

More Information
UPC 810086014835
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