Perfect Corals Kalkwasser: Medical Grade Calcium Hydroxide
Transform Your Tank with the Simplest Two-Element Dose
Looking for a reliable, low-maintenance way to keep calcium and alkalinity in check without juggling a two-part system every day? Kalkwasser has been a reef tank staple for decades, and for good reason. It's one of the most cost-effective dosing additives available, and when dialed in correctly, it handles calcium and alkalinity simultaneously while giving your pH a natural lift.
Perfect Corals sources medical grade calcium hydroxide, meaning you're getting a high-purity powder free from the contaminants that can sneak into lower-grade formulations and wreak havoc on your reef chemistry. Whether you're running an ATO reservoir, a dosing pump, or a dedicated kalkwasser reactor, this dissolves cleanly into RO/DI water and delivers a stable, saturated solution to your saltwater aquarium. The result is a balanced method that supports coral calcification, maintains carbonate alkalinity, and keeps your pH from drifting low, especially effective when dosed overnight during the pH trough.
QUICK STATS & DOSING GUIDE
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Details: Medical grade calcium hydroxide (Ca(OH)₂); high-purity dry powder
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Dosing instructions: Mix ½ tsp to 2 tsp per gallon of RO/DI water; stir lightly and allow to settle 20 to 30 minutes before use. Start low and adjust in ½ tsp increments based on tank demand. Target pH 8.3 to 8.4; never exceed 8.5. See full dosing guide below for ATO, dosing pump, and reactor methods.
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Form: Fine dry powder
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Shelf life: Store sealed, dry, and away from CO₂ exposure to preserve potency
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Best for: Reef tanks needing balanced calcium and alkalinity maintenance with minimal equipment; ideal complement to ATO systems
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Compatibility: Compatible with all marine aquarium setups; can be used with ATO reservoirs, dosing pumps, or kalkwasser reactors
WHY BUY FROM THE CORAL BOUTIQUE?
At The Coral Boutique, we don't stock products we haven't vetted. Kalkwasser is a foundational part of how many of us here manage our own reef tanks, and medical grade purity is non-negotiable. When you buy from us, you're getting the same additive we trust in our own systems.
