Brightwell Aquatics

Florin Delta KH+ Alkalinity Supplement for Freshwater and Planted Aquaria - 250 g - Brightwell Aquatics


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Alkalinity in freshwater systems helps to stabilize the pH, as they are correlated; the greater the KH (alkalinity), the less likely the pH changes.  Adjusting and maintaining alkalinity to a value or range appropriate to the requirements of the organisms residing within an aquarium is vital to their long-term care; consult a reputable reference source citing these requirements prior to use of this or any other pH - or alkalinity - altering supplement.


  • Increases alkalinity (a.k.a. carbonate hardness or buffering capacity) in freshwater aquaria with a target pH of 7.8 or less
  • Improves stability of pH
  • Safe for use in all freshwater community and planted aquaria
  • Composed of USP-grade ingredients
  • Contains no phosphate-based buffering agents

Instructions and Guidelines:

  • Do not add this product directly to an established aquarium without first diluting in water as directed, and without first determining pH and alkalinity with an accurate meter or test kit.
  • Read entire instructions before proceeding.
  • Adjust alkalinity, pH, TDS, and temperature of the water prior to adding it to an established aquarium.
  • Aquarium addition:
    • Dilute 1/4-tsp in ~16 fl-oz. (or ~500 ml) of purified water and mix well; add the resulting solution to the aquarium at the rate of 1 fl-oz. per 5 US-gallons (18.9 L) every two hours until alkalinity has increased 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 alkalinity of the system (faster circulation will decrease the time required for alkalinity to change), and that alkalinity 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 alkalinity of greater than 1 dKH per hour. 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. pH may be further adjusted through the use of an appropriate acid or base solution (such as Brightwell Aquatics Florin pH- and pH+, respectively).
  • Tap and/or purified water addition:
    • Adjust alkalinity of water to desired value with Florin Delta KH+; once alkalinity has stabilized, add Florin pH- or pH+ until desired pH is attained. Finally, adjust TDS of water (such as with Brightwell Aquatics Remineraliz or Remineraliz-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 carbonic acid salts; do not taste, swallow, or breathe dust, and avoid contact with skin. If swallowed: give water, get medical attention. May cause eye or skin irritation. If in eyes, flush with water for 15 minutes, get medical attention. If on skin, wash thoroughly with water. Keep out of reach of children. Not for human consumption.

Manufacturer Info

Brightwell Aquatics Aquarium Supplies
The goal of Brightwell Aquatics is to provide the absolute highest quality, scientifically-sound products and customer service of any aquarium water care manufacturer, and to do it all in a straight-forward and honorable fashion. All Brightwell products are formulated by marine scientists with a passion for the aquarium hobby. They utilize the highest purity ingredients in concentrations that provide the most use to hobbyists. Nearly all Brightwell Aquatics products are over 99.9% pure. The usage guidelines of Brightwell Aquatics products are written in plain language but the company is always available to answer consumer questions. All products are lot numbered for quality control and customer service.

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