[borderglider]

I hate to give you the bad news but you will have to take all that turf out of your pond - otherwise it will rot and produce a eutrophic condition in which you will have fantastic algal blooms and no oxygen. Sorry to have to tell you this - sounds like a disaster.

When making ponds the general advice is to do everything possible to keep them 'nutrient poor' - for example you never put topsoil or rich soil of any kind into the water. If you put topsoil into a pond you are in effect making 'soup'. When they make large ponds they always use SUBSOIL for any soil input - since this is largely mineral with no organic remains or nutrients in it. On my early attempts to make ponds - 20 years ago - before I knew about this , I just used topsoil and created huge bowls of green algal soup with no life in them - apart from algae.

Your best option is to remove the turf and start again - awful though that is to hear. Your local wildlife trust will have good practical advice on pond construction and there are numerous books to consult. Good luck.