Hobby Lime wood air diffusors produce particularly fine bubbles. They are highly durable and made from Lime wood which has been long matured. They are often used in protein skimmers.https://www.aquaristikshop.com/aquaristic/Hobby-Lime-wood-diffusor/101500/
- Mikael L. wrote about Hobby Lime wood diffusor in 2016:
Works really good and easy to clean.
Made of natural basis.