The Aquabus is only used to expand an Aquaero with additional connections, e.g. a QUADRO or a D5 NEXT, these devices connected via Aquabus are then controlled directly via the Aquaero.
Without an Aquaero the Aquabus is not usable.
From my point of view, you can skip the control of the pump completely, it does not bring you much, except varying background noise.
It is better to set a fixed speed that gives you the desired flow and the best soundscape for you.
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