Aquarium top up is a simplified system to manage the evaporation in the aquarium. The basic principle of aquarium top up is that a float switch in connected to a valve and a pump. When the float switch goes down it opens the valve and turns on the pump. I like the idea of aquarium top up but it can a pain to set up depending on how you do it but it does offer a huge amount of flexibility and will greatly simplify your water management.
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