Backyard Aquaponics
A place to discuss aquaponics

Check out this site.

http://finnbuilder.co.za/v2/?q=node/19

They even have a curved mould that could be used for ponds. Looks so easy maybe even I could build with it !!

Easy to make as well. I wonder if you can make one that will work with steel rod going through it or to work around mesh. When they make those concrete walls for the highway they use a lot of steel to stop them cracking.
I was going to make something similar for garden beds. Big funnel on top for the concrete to be added and an air jackhammer hooked up to the frame to vibrate it forward. Just keep adding the mix to the top and point in the right direction.

Slip form is used in many concrete constructions...
In fact the largest continuous pour in southern hemisphere
was in bunbury. The Wando platform (gas) was 72 mtrs tall had 4 towers
that became gas tanks. It was 'tugged' 1700 ks to where it now sits
on the bottom of the ocean. (working)

The finn builder is not new, I made a similar looking thing to add a topping to a rammed earth wall for a client...
That said if used correctly I am sure I will help heaps.