I have to say that, since last talking to Nammy and Nammy being a believer in heavy water movement, my tank seems to be less dependent on the PS.
That said, I have one tank with a Remora Pro which works great, is hang on, does not cost an arm and a leg, but needs a little DIY gadget (simple) to make it operate more quitely - it is otherwise very noisy!
I also have a home made version made of 3" PVC made by Jaze (still thank you Jaze) which worked very well on my downstairs prop tank.