it is merbau decking

Thanks! Very nice colour. What stain/oil it you use?

Can you please give me the width of the boards as well as the gap in between?

these are 90mm boards with a minimal gap of around 4mm.

Thanks. Are you able to explain your rationale behind choosing the wider boards with minimal gap? Also, is there a boundary wall behind the timber "wall"?

The 90mm board is a standard decking board, with the 4mm gap being enough to allow for expansion and movement. The timber wall is about 3m from the boundary, with a service area behind it with all of the filtration equipment.

Thanks, team!