This item is drop shipped directly from Deltec USA and will be delivered within 1-3 weeks from the date they ship. Once the order has been processed and shipped, we are unable to cancel any items on the order without the 20% restocking fee applied.
Available for shipping within the contiguous 48 USA states only at this time.
The Deltec KM500 Kalkwasser Stirrer is designed to produce a saturated solution of kalkwasser, also known as limewater, for maintaining calcium, alkalinity, and pH levels in reef aquariums.
The KM500 can be used as a stand-alone supplementation method or alongside a calcium reactor to help counteract low pH. Its compact design allows for installation in or near your sump, making it a practical solution for automated kalkwasser dosing.
A kalkwasser stirrer provides a clean, controlled way to deliver saturated kalkwasser to a reef aquarium. Kalkwasser, also known as limewater, helps replace calcium and alkalinity consumed by corals, coralline algae, and other calcifying organisms, while also helping support a higher, more stable pH.
Instead of manually mixing kalkwasser in a top off reservoir, the stirrer keeps calcium hydroxide contained in a dedicated chamber. Fresh RO/DI water passes through the reactor and becomes saturated before being added to the aquarium. This helps keep the top off reservoir cleaner, reduces manual mixing, and limits exposure of the kalkwasser solution to air.
Auto Top Off
Connect your automatic top off system to your kalkwasser stirrer so evaporated water is replaced with saturated kalkwasser. This is a simple and popular setup that allows kalkwasser dosing to happen automatically without the need for a dedicated dosing pump. Because delivery is based on evaporation, the amount dosed can vary from day to day, so regular monitoring of pH, calcium, and alkalinity is recommended.
Dosing Pump
While many aquarists connect a kalkwasser stirrer to an automatic top off system, the most consistent approach is often to feed the stirrer with a dosing pump. A dosing pump allows a fixed amount of kalkwasser to be delivered throughout the day, independent of changes in evaporation. This provides more predictable supplementation and helps reduce the risk of pH, calcium, or alkalinity swings.
Connect the top off or dosing pump to tap No. 8 on the inlet side of the stirrer. The outlet from the stirrer should gravity drain into the sump. To prevent backflow, install a check valve between the top off pump and the stirrer.
Using the Kalkwasser Stirrer
Important Notes
Maintenance
When the calcium hydroxide has been depleted, as indicated by a reduced pH value, switch off the pump and disconnect the tubing from the stirrer.
Clean out any remaining calcium hydroxide, refill with fresh calcium hydroxide, and repeat the setup steps.
Deltec KM500 Kalkwasser Stirrer