We got a local company Aqua Techniques to quote to sort it out and although it was quite expensive we decided to go ahead and last week they came and sorted it for us. They are a really good company and I wouldn't hesitate to recommend them. They have a structured approach and do exactly what they say they will when they come to appraise the job.
They erected a huge fish tank to transfer the fish whilst they completely emptied and dredged the pond. Sadly most of our goldfish had disappeared and we think they were taken by the heron. There were only three large goldfish left (there used to be at least twenty) and our Koi Carp 'Sharkey'. There were also about a dozen small goldfish still black in colour and very tiny, it's 50/50 whether they'll get to grow up as the larger fish will eat them given the chance.
The pond was full of silt, about a foot deep so all of that had to be removed and spread onto the borders in the garden. All the plants were taken out because they had over grown and the guys split them down and re-planted sections of the pond. At the moment it is totally bare as all the plants have been cut right back but they will grow again in the spring but it will be much more structured. They put a net on the pond for us which will serve two purposes: one to stop the leaves filling up the pond as we head into the main falling period and also to stop the heron from stealing any more fish. I feel a bit sorry for the fish as they've nowhere to hide at the moment but I'm told this isn't a problem and that they will just go to the deepest part of the pond when they want to rest.
It was a big task but they completed it by 6.00 pm and it's such a relief that it's done.
Here are some pictures of before, during and after!
Emtpied out and all the silt removed by hand. This took a lot of time to do carefully so as not to damage the liner