Any trickle tower/shower media has the potential to build up if the conditions permit. More an issue of pre-filtration,filter design and flow rates. Lava rock is still the most widely used material due to performance, cost and availability. A properly designed shower needs little to no maintence even with lava rock.
In my area feather rock is difficult to find. Just like lava rock it's a natural product that varies greatly in colors, density and porosity. If buying bulk it is a PIA to cut or break into shower sized pieces.
Last edited by batman; 02-21-2021 at 07:33 AM.
The real Batman wears polyester! Don't be fooled by the plastic imposter.