Mini day in the life: Pond cleaning (Patreon)

If anyone has any suggestions on how to clean the pond then please comment below. I had a pond before but it had a pump and the water was somewhat clear. This water is so dirty on the bottom and tonnes of leaves laying on the bottom too. I have ordered a pump/fountain to see if that helps but may need to empty the pond, dont know where the fish is and I dont want to accidentally kill him :( called him Nemo