I wonder if you could achieve the same effect more easily/consistently using cement. It's basically how aquifers "filter" water. Limestone is naturally permeable unlike fired clay.. were you need to control the porosity. I'd imagine cement mixtures are much easier to handle and you can make arbitrary shapes (higher surface area and higher hydraulic pressure to increase the flow rate)
ChrisMarshallNY
When I was a kid, we'd go camping, and we had these water filters that you would pump water through, and they would filter it.
It was ceramic, and I think it was the same idea, but we used a pump to force the water through (like a bicycle pump).
Ceramic filters are very common in Brazil, used in clay recipients which also keep the water cool even in summer without spending energy.
https://g1.globo.com/saude/noticia/2026/03/14/filtro-de-barr...
There is a company[1] in Indonesia that actually makes very nice versions of this tech.
[1] https://www.terrawaterindonesia.com/
I wonder if you could achieve the same effect more easily/consistently using cement. It's basically how aquifers "filter" water. Limestone is naturally permeable unlike fired clay.. were you need to control the porosity. I'd imagine cement mixtures are much easier to handle and you can make arbitrary shapes (higher surface area and higher hydraulic pressure to increase the flow rate)
When I was a kid, we'd go camping, and we had these water filters that you would pump water through, and they would filter it.
It was ceramic, and I think it was the same idea, but we used a pump to force the water through (like a bicycle pump).
Got hackernewsd
http://archive.today/2026.08.13-052756/https://wiki.lowtechl...
Further reading: https://grokipedia.com/page/Ceramic_water_filter