Once reasonably clear, a hole was punched through the wall and the two 110mm drains and the two airline tubes were brought into what would eventually be the filter house.
The returns were buried in the ground and insulated. Here they are at the point where the are about to be punched through the wall of the old pond into what will be the filter house.
Only around half the area of the old pond will be used as a filter house, the front part will be filled and covered with decking. Here I've started to extend the pipes into the correct place. A dividing wall will soon be built across the pond roughly where the old bottom drain was.