Reef Angel users rejoice, Reef Angel has just recently released a water level expansion kit for their Reef Angel controller. The Reef Angel water level expansion kit relies on water pressure, which simply put means you can say goodbye to your mechanical float switches. The pressure sensor plugs straight into your existing Reef Angel head unit, and unless you decide to get several does not require any expansion units. The actual water level unit and its associated electronics are not suspended underwater, and actually relies on a piece of air tubing within a nine inch 1/2” PVC pipe to make it’s readings.
The use of the PVC pipe does mean that the water level sensor takes up more space in your sump, but the lack of moving parts or submerged electronics does mean that potential failures will be a lot less unlikely. What’s especially interesting about the new Reef Angel pressure sensor is it’s variable ability to measure water level by percentage rather than the usual on/off encountered with float switches – so you know how long you have to make up for evaporation.
Using a sensor a high degree of resolution, the module can detect change as small as o.08 mm within the provided 9 inch pipe. Rounded up with a generous error factor this comes down to an accuracy within one percent. A 1% accuracy might not be needed for most applications, but we can imagine it to be very useful in surge tanks or for automatic water changes. Conventionally float switches cannot be used in systems with wavemakers or surge system (unless used in the sump) because of the constantly shifting water level. We assume that with the Reef Angel device the shifting water level would be predicable and water could be topped off based on an overall dropping level of shifting water. For automatic water changes the pressure sensor would both be much more accurate and could additionally account for water evaporation.
The Reef Angel water level sensor expansion is currently available at the Reef Angel web store for $69. For more information be sure to check out the Reef Angel website and Forums.