Seachem Kalkwasser

Seachem Kalkwasser

Seachem Kalkwasser is a high-purity calcium hydroxide limewater mix for marine aquarium keepers maintaining calcium levels close to natural seawater concentrations. It is designed for use in top-off water and can increase pH without directly affecting carbonate alkalinity.

Key Benefits

• Pure calcium hydroxide with high purity and solubility characteristics.
• Prepares kalkwasser or limewater solutions for direct calcium maintenance.
• Helps maintain calcium directly while supporting carbonate alkalinity indirectly.
• Can be used to raise pH without impacting carbonate alkalinity.
• An economical option for reef aquarium calcium supplementation.

How to Use

• Never add Seachem Kalkwasser directly to the aquarium.
• Mix the required amount with water, allow the solution to settle, then drip only the clear supernatant (top solution) into the tank.
• Do not allow undissolved material to enter the aquarium.
• Adjust the drip rate to maintain a stable pH of 8.3–8.4.
• Keep the container tightly closed and minimise solution-to-air contact to reduce calcium carbonate formation.

Dosage

• Add 3 g (1 teaspoon) to 4 L (1 gallon*) of water and mix to dissolve.
• When using pure water, prepare a fully saturated solution with 6 g (2 teaspoons) per 4 L (1 gallon*).
• Adding 4 L (1 gallon*) of saturated kalkwasser solution to 150 L (40 gallons*) raises calcium by 24 mg/L.

Suitable For

Marine and reef aquarium systems where evaporation rate and CO2 concentration allow kalkwasser to maintain calcium and support alkalinity. Kalkwasser can be an effective maintenance method, but it requires diligent monitoring and may be more challenging for beginners.

Compatibility

If additional calcium is required, use Reef Advantage Calcium™, Reef Complete® or Reef Calcium™. For carbonate alkalinity, use Reef Builder™ or Reef Carbonate™. Do not mix these products directly with a kalkwasser solution.

Frequently Asked Questions

Can I add Seachem Kalkwasser powder straight into my marine tank?
No. Never add it directly to the aquarium. Prepare the limewater solution separately and drip only the clear top solution into the tank.

How much Seachem Kalkwasser should I mix for regular limewater?
Mix 3 g (1 teaspoon) with 4 L (1 gallon*) of water. For a fully saturated solution made with pure water, use 6 g (2 teaspoons) per 4 L (1 gallon*).

What aquarium parameters should I monitor when using kalkwasser?
Monitor pH and carbonate alkalinity, and adjust the addition rate to maintain pH at 8.3–8.4. Magnesium concentration should also be monitored and maintained.

Will kalkwasser affect carbonate alkalinity?
It increases pH without directly impacting carbonate alkalinity, while kalkwasser solutions maintain calcium directly and carbonate alkalinity indirectly.

Why is there chalky build-up in my aquarium or plumbing?
Kalkwasser use can increase chalk build-up on substrate and plumbing surfaces. More frequent cleaning may be needed to keep aquarium equipment functioning properly.

Are there handling precautions for Seachem Kalkwasser?
Avoid contact with or breathing the dust. Do not eat it or get it in your eyes. If contact occurs, flush with water for 5–10 minutes; for eye contact, wash immediately with water and seek medical attention.

When can I expect delivery?

• Gauteng (Jhb/Pta) - 1-3 working days
• Nationwide (Cpt/Dbn+) - 2-5 working days
• Outlying Areas - 3-7 working days

All orders are sent via Economy Road, typically through Fastway or Internet Express Couriers*. Estimated timeframes are not guaranteed. Once the order is collected by the courier, we have no control over third-party logistics and cannot make any time promises.

If you prefer a faster 🚀 shipping option, we also offer The Courier Guy during checkout in the dropdown selection. Please note that this option is not free, and you must choose it to use it. Please pay careful attention to the cutoff times and delivery timeframe for these options during checkout.

Enjoy the convenience of collection points and lockers! 📦

No more waiting at home or at work for your delivery. Simply choose a collection locker or pickup point and collect your order when it suits you.

Delivery times to lockers and pickup locations typically range from 2–7 working days, depending on your location.*

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Collection timeframes:

• Bob Box: Collect within 2 days of receiving your collection notification.
• PUDO Lockers: Collect within 36 hours of receiving your collection PIN or SMS notification.

If a PUDO parcel is not collected within 36 hours, it will automatically be transferred to the nearest PUDO Kiosk or Depot at no additional cost. The parcel will then be held there for approximately 2 days before being returned.

Please ensure you collect your parcel within the applicable collection period. Uncollected parcels will be returned to the sender, and additional shipping charges may apply should the order need to be resent.