Reef Buffer 1 kg — Buffer pH 8.3 pK 8.6 Reef | Seachem

Seachem Reef Buffer in a 1 kg format is a powdered buffer specifically designed for reef systems. Formulated with a blend of carbonates and bicarbonates, it produces a pK of 8.6 in seawater. This high pK counteracts the constant acid pressure generated by the organic load of corals, fish, and invertebrates, helping to stabilize the pH at 8.3. The 1 kg format is the economical choice for reef aquarists who regularly adjust the pH of their system.

Main advantages

• pK of 8.6 in seawater — formulated for reef environments, not fish-only systems
• Stabilizes pH at 8.3 without risk of accidental overshoot.
• Simultaneously increases pH and carbonate alkalinity
• Economical 1 kg format for systems requiring frequent pH adjustment

Use in reef aquariums

In a reef aquarium, the organic acids produced by the inhabitants force the pH down much more than in a fish-only system. Competing sodium bicarbonate-based products have a pK of 8.3, too low to compensate for this pressure—they maintain the pH between 8.0 and 8.2. The Reef Buffer's pK of 8.6 overcomes this limitation. The Reef Buffer also increases carbonate alkalinity. However, when only alkalinity needs to be adjusted without changing the pH, Seachem recommends Seachem Reef Builder or Seachem Reef Carbonate.

Dosage

• Check the pH and alkalinity before each use
• 5 g (1 level teaspoon) per 150 L (40 US gallons) increases the pH by 0.1 unit and the alkalinity by 0.5 meq/L
• Dissolve in at least 250 ml (1 cup) of fresh water, then add to the container
• Frequency: every 2 weeks to twice a week depending on system demand
• The alkalinity must not exceed 6 meq/L

Ionic balance diagnosis

If the alkalinity reaches 6 meq/L without the pH reaching 8.20, or if turbidity persists for more than 15 minutes after titration, the system is ionically unbalanced. To restore balance: perform a water change or adjust the magnesium and calcium levels to achieve a Mg:Ca ratio of approximately 3:1.

Manufacturer's precautions

• Do not exceed the recommended dose without checking the pH and alkalinity.
• Excess alkalinity can accelerate the loss of calcium, magnesium, and strontium.
• Do not mix directly with a calcium, magnesium, or strontium supplement — alternate days or wait at least 30 minutes.

Available formats

• 50 g
• 250 g
• 500 g
• 1 kg
• 4 kg

Why choose the Reef Buffer from ReefSolution?

The 1 kg format is ideal for reef aquariums that require regular pH adjustments. Combine it with Seachem Reef Builder for independent alkalinity control and Seachem Reef Advantage Calcium for calcium. Monitor your parameters with the Salifert KH/Alk Test Kit or the Hanna Checker Alkalinity.

Frequently Asked Questions

When should you use the Reef Buffer instead of the Reef Builder?

Use the Reef Buffer when both pH and alkalinity need to be increased. Use the Reef Builder when only alkalinity needs to be corrected without changing the pH. The two products can be combined for independent control of each parameter.

Is the Reef Buffer more effective than the Marine Buffer for a reef tank?

Yes. Marine Buffer has a pK of 8.3, which is insufficient to compensate for the high organic load of a reef. Reef Buffer, with its pK of 8.6, is specifically formulated to achieve a stable pH of 8.3 despite the organic acid production of corals and invertebrates.

My pH isn't rising despite the Reef Buffer — what should I do?

If the alkalinity reaches 6 meq/L without a pH of 8.20, the system is ionically unbalanced. Perform a water change or adjust the magnesium:calcium ratio to approximately 3:1. Do not continue dosing beyond 6 meq/L of alkalinity.