I would not do this, because u need a minimum pressure or flow otherwise you will cook your hoses
i mean to say your pump is spinning but the pressure istn enough for a circulatio of the water in your sytem
Ever used a Laing? Still at 7V it has more power than an aquastream

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@Topic: I don't think so, the Relay can switch the pump on and of. BlackShorty invented a circuit for the automatic reduce of the power after a few seconds, maybe you/he can modify it to reduce the power by an external signal (like a fan-connector from the auqaero -> but don't connect the laing direktly to a fan-output, that would be to much for the ae).