Hey Jairun, welcome!
There's one other useful thing I plan to measure when I manage to get around to building my own controller. If someone else uses the idea first, I don't mind.
As the physical load increases on a constant speed motor, so does the current required to maintain that speed. Compared to more common motors, the effect is quite a bit smaller in mag drives, like those used in filters. But it's still detectable. I can see it with the filter plugged into a Kill-A-Watt meter. Would love to have a little warning pop up saying when it's time to clean the media, rather than noticing reduced flow alone; which I often miss.