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Seachem Reef Carbonate


Concentrated (4,000 meq/L) optimized blend of carbonate and bicarbonate salts designed to restore and maintain carbonate alkalinity (KH) in the reef aquarium.

Calcium and carbonates are essential to all coral growth. If either becomes deficient, coral growth will cease, followed by a rapid decline in coral health. To prevent this you must provide carbonates (Reef Carbonate below) and calcium ( Reef Advantage Calcium or Reef Complete below).

Used as directed, Reef Carbonate™ will not deplete calcium, magnesium, or strontium which usually tend to precipitate with increasing alkalinity. Reef alkalinity should be maintained at 3-5 meq/L (8-14 dKH). Alkalinity should not be allowed to fall below 2 meq/L.

Why Reef Carbonate??

Whereas competing products simply use sodium bicarbonate, Reef Carbonate™ is made with a blend of carbonate and bicarbonate salts. This blend of salts results in Reef Carbonate™ yielding a pK of roughly 9.0 in saltwater (higher than competing products).

In a closed reef system, the multitude of organics produced by reef inhabitants tends to force pH downward, but the advantage of Reef Carbonate’s™ higher pK is a stabilization of pH around 8.3-8.4. Competing products’ formulations make them incapable of such a claim, so pH will always fall below desirable levels for a reef aquarium.

Seachem Reef Carbonate Directions

  • Beginner Use 1 capful (5 mL) per 80 L (20 gallons) twice a week. Best if diluted into a cup of freshwater, then added. Check alkalinity every 2 weeks and adjust dose or frequency accordingly.
  • Advanced Check alkalinity, then follow dosing regimen above until alkalinity is adjusted to 4-5 meq/L. Each dose will raise alkalinity by about 0.25 meq/L. Size or frequency of dose can be adjusted, but do not exceed 1 meq/L per day. Thereafter, use as required to maintain alkalinity.
  • Expert After determining the alkalinity consumption rate, set up a continuous drip system. Use the following formula to determine how much to add to your top-off water: m=va (m=mL of product to add to top off water, v=volume of tank in gallons, a=amount to raise alkalinity in meq/L). For example, if you want to raise alkalinity by 1 meq/L in a 50 gallon tank, then you would add 50x1=50 mL into the top-off water.
  • Hints Best to pour in gradually near strong water movement. Do not add to a sump or other area of slow water exchange.

Do Not Overdose: Excess alkalinity may enhance the loss of calcium, magnesium, and strontium. Do not directly mix with any calcium, magnesium, or strontium supplement. Best if calcium & carbonate additives are added on alternate days or at least 30 minutes apart.