Koi keepers use exactly the same principle... called Bakki Showers...
Attachment:
bakki_installed (Medium).jpg [ 36.66 KiB | Viewed 1562 times ]
Filled with media... they also provide filtration...
Attachment:
Bakki-Filters-bottom-20holes (Medium).jpg [ 68.43 KiB | Viewed 1563 times ]
They're basically a "trickle tower".... but do suffer some evaporative loss...
On the other hand... they can provide a degree of "cooling"... and (as above) filtration...
I use a single half drum in my mega system...
Attachment:
100_1488 (Medium).JPG [ 82.87 KiB | Viewed 1555 times ]