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Seachem Reef Builder
Seachem Reef Builder™
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Reef Builder™ raises carbonate alkalinity without immediately impacting on pH. With long term use there will be a tendency to stabilize at pH 8.3. Carbonates and calcium are essential to all coral growth. If either becomes deficient, coral growth will cease, followed by a rapid decline in coral health. Used as directed, Reef Builder™ will not deplete calcium, magnesium, or strontium which usually tend to precipitate with increasing alkalinity. Reef Builder™ and Reef Buffer™ may be used together. Use Reef Builder™ to raise carbonate alkalinity without affecting pH. Use Reef Buffer™ to raise carbonate alkalinity and pH.

Sizes: 250 g, 500 g, 1 kg, 4 kg

Why It's Different

Unlike the competition, Reef Builder™ contains calcium, magnesium, and strontium to compensate for the inevitable loss which occurs when raising alkalinity. It also contains sufficient magnesium to restore magnesium routinely depleted.


BEGINNER: Use half a level teaspoon per 150 L (40 gallons) twice a week. Dissolve in at least one cup of freshwater. 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: t=0.05va (t=teaspoons 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 your alkalinity by 1 meq/L in a 50 gallon tank, then you would add 0.05x50x1=2.5 teaspoons into the top-off water.