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EVAPORATION CONTROL & WATER REPLENISHMENT

Replacing evaporated water is a constant chore to the majority of aquarists, but things can be made easier with an electronic automatic top up system. For marine and reef aquarists a steady water chemistry is essential and evaporation will cause shifts in system salinity, as it is only the water that evaporates and not the salts, so a continual replenishment of lost water is required.

To operate a sump based system installing such a device is relatively straight forward. Firstly you need to ascertain how much water is being lost, say on a daily basis, but this will probably fluctuate over a yearly period ie summer and winter and central heating etc. Secondly a suitable container, non toxic for storage of the top up water (R/O or DI) will need to be added to the system. A float switch located in the sump or main aquarium will then activate a submersible pump that pumps sufficient water to push the float switch into the off position and thus, stopping the pump.

The above is a simplified explanation of the process but, moving on and depending on the model of the top up system employed, additional control options can be used. kalkwasser mixers or stirrers have more recently come on to the market and a top up system can be used in conjunction with these. The benefit here is to add calcium and alkalinity to the system water (best at night to control Ph) in the form of evaporated water. Another advancement is to add a calcium carbonate based material (aragonite etc) into the top up reservoir and by adding R/O water, which has a neutral PH, will assist in dissolving elements and buffers. A liquid aragonite could be added manually to the top up reservoir for similar results. Advanced systems have additional floats to monitor high or low water levels in sumps and audible alarms to warn aquarists of faults.