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alkalin8.3p container

Brightwell Aquatics - Alkalin8.3-P

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KH Buffer Powder for all Marine Fish and Reef Aquaria


  • Raises alkalinity, adjust pH to 8.3
  • Unlike single component KH products such as sodium carbonate, Alkalin 8.3P is a multi-component automatic buffer that regulates pH and its use makes for a much more stable aquarium.  Eliminates pH and KH instability caused by poor salt mixes and ineffective buffering products.
  • Highly-effective alkalinity-increasing (”buffer”) powdered blend.
  • Helps increase pH stability in an aquarium by raising the alkalinity; continued addition raises pH until 8.3 is reached, at which point the pH remains unchanged and the alkalinity alone increases.
  • Provides a source of carbonates, which make up the majority by weight of aragonite, the mineral secreted by reef-building organisms as skeletal material.
  • Formulated by a marine scientist.
  • Determine alkalinity in aquarium with an accurate test kit prior to supplementing. Do not add this product directly to an aquarium without first diluting in water as directed

Technical Background

Alkalinity, also referred to as carbonate hardness or buffering capacity, is essentially a means of quantifying the stability of pH in a solution, such as aquarium water. In an aquarium, weak acids formed by oxygen respiration and the decomposition of organic material gradually deplete alkalinity. If left unchecked, the alkalinity drops below a critical level and pH begins to fluctuate more wildly than is normally suggested (a daily pH shift of +/-0.2 is normal in marine aquaria), causing stress to livestock. Alkalinity is also depleted by reef-building organisms during the production of aragonite (~60% carbonates by weight), and is therefore very important for their rapid growth. Maintaining the alkalinity in marine aquaria between 7.5 - 9.5 dKH (2.7 - 3.4 meq/L) will generally maintain pH within the desired range.

Instructions and Guidelines

Basic: Dissolve 2 grams (~½ teaspoon) of product per 20 US-gallons of aquarium water in 8-fl. oz. of fresh water; add every other day or as needed to maintain the alkalinity within a range of 7 - 12 dKH. When used in this fashion, 1,000 g treats up to 10,000 US-gallons (37,854 L).

Advanced: Determine the alkalinity in the aquarium using an accurate test kit before supplementing. Each g of Alkalin8.3-P will increase the alkalinity in 1 US-gallon (3.785 L) of water by 12 dKH (4.2 meq/L).]

EZ Calculations: For dKH: Multiply tank capacity in gallons x dKH increase desired x .089 = grams of product to add. Example to raise the alkalinity by 1.2 dKH in a 50 gallon tank the calculation is: 1.2 x 50 x 0.089 = 5.35 grams or 1 teaspoon. For meq/L: Multiply tank capacity in gallons x meq/L increase desired x .25 = grams of product to add. Example to raise the alkalinity by 0.5 meq/L in a 50 gallon tank the calculation is: 0.5 x 50 x 0.25 = 6.25 grams or 1.2 teaspoons.


Problem pH Aquariums:  Aquaria with low circulation at the water’s surface, or in which a CO2-injected calcium reactor is being employed, or which are placed in an enclosed room with human and animal inhabitants (giving off CO2 into the air), often have a depressed pH due to carbon dioxide build up. Boost pH+ can help overcome this along with other other measures, such as providing outside air to the skimmer intake port or other methods to control CO2 and bring pH in the aquarium back into a higher desired range without raising alkalinity to an unacceptable level. Use Boost pH+ as directed and do not exceed a pH value of 8.5, because pH at 8.6 or higher may be stressful and/or damaging to sensitive aquairum inhabitants. Additionally, changes to pH should be made very gradually, again to avoid stressing aquarium inhabitants. See suggestions for adjusting alkalinity below. It is not unusual for pH to fluctuate throughout the course of 24-hours between seemingly wide-ranging values (i.e. lower at night higher during the middle of the day); this is a natural occurrence that is caused by changes in the rates of photosynthesis between dark and light periods. If pH levels are seen to be constantly below the desired level and alkalinity is within the proper range, then the addition of Boost pH+, this product, may be very helpful.



Caution: Contains carbonate, borate and bicarbonate salts; harmful if swallowed. 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


Inorganic salts of carbonate, bicarbonate, sulfate, borate salts,  & proprietary ingredients.

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