Casuarina pods/cones are an Australian native alternative to Alder cones.
As well as being a natural décor they also provide other positive reasons to add them to your tank. They grow bio film which is shrimps favourite food whilst also providing an interesting foraging surface. They release tannins which is antibacterial and anti fungal. Tannins also naturally lower the PH. The small spaces provide a perfect hiding spot for shrimplets. They also contain humic acids.
Due to being a natural product they vary in size and shape. They are approximately 2 - 3cm long and approximately 2 - 3cm wide.
Give a really good rinse or add to boiling water for a few minutes. May take a few hours to a few days to waterlog and sink.