I was just looking at their catalog this morning. It is in there.
I am trying to determine if I can use ultrasonic level sensors in my RAS. A bit more digging I suppose.
If you keep it dark enough algae is not an issue.

I have absolutely none in my indoor systems.
My aquaponic set up that is outside will use a UV clarifier plumbed in. I don't want my plants competing with FA for nutrients and nitrates.
I'd be worried about potential stress on fish with this device in tanks as sound travels better in water than in air.
And I'd be concerned if this was effective at all I would think it would be most effective in small ponds -- very small ponds.