It is concrete with 8" thick side walls.

Thank you! I have a very narrow yard and I was hoping to put in a decent width terrace AND a small, narrow pool and this look would be great. I looked at your website - really nice work, loving the flow, even on difficult sites.

You must love your work. For 8'x4'x1' raised beds - what is the minimum thickness you would recommend? would you use AR fibres within your concrete?
Kind regards greenmoss

For water features I would recommend a minimum of 6" reinforced (rebar) concrete for sidewalls and 8" thick floor. We usually do 8" sidewalls for water features. If it is only 8'x4'x1' deep you could probably do 4" sidewalls if you used high strength concrete and good reinforcing. I would keep the base at least 6" thick though.

Great looking water features, are you able to keep the concrete bare on the interior, or do you have to coat it with something thicker to add a waterproof sealant or membrane of some sort?