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βš—οΈ Alkalinity Dosing Calculator

Calculate how much alkalinity supplement to dose to reach your target dKH.

SPS: 7.5-9.0 dKH, LPS: 8-10 dKH
Results
Dose Amount
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Add gradually β€” never raise more than 1 dKH per day
Alkalinity Change
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Total meq
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Note
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meq needed = Ξ”dKH Γ— 0.357 Γ— Liters
Soda Ash: 1 tsp per 10 gal raises ~1 dKH
Safety: Never raise alk more than 1.0 dKH in a single day

Understanding Alkalinity in Reef Tanks

Alkalinity (dKH) measures the buffering capacity of your water and is consumed by corals for skeleton building. It's the single most important parameter to keep stable in a reef tank.

Target Ranges

Tank TypedKH RangeStability
SPS Dominant7.5 – 9.0Β± 0.3 dKH daily
Mixed Reef8.0 – 9.5Β± 0.5 dKH daily
LPS / Soft8.0 – 11.0Β± 1.0 dKH daily

Dosing Methods

Two-part dosing (soda ash + calcium chloride) is the most common method. Kalkwasser dripping is economical for low-demand tanks. Auto-dosing pumps like the Neptune DOS or GHL Doser provide the most consistent results for SPS-heavy systems.