u/AmberDucky

Hey everyone. We have bought this house recently and will be able to move in in two months. The former owner still lives there for now but has allowed us to care for the garden already (how nice of her).

The house comes with this pond which is covered in algae. There are goldfish living in it and I'm scared they will suffocate before we move in. The pump doesn't really aerate the pool as far as I can see and the only plants are water lillies. There is a pump that pumps ground water into the pond but it's not running continuously, just to fill it up a little when water evaporates. The pond lining is soft sheets, and as far as I know there is no substrate (only lots of fish poop). The pond is 1.4 m deep in the middle.

My question is if this is a bad setup, how to improve it and how to take care of it. I've already removed a lot of the algae (last pics) and am planning to buy more plants. Does the ground need rocks? Do I need a different pump for air? How often so I need to remove fish poop? Which plants to add (preferably native to Germany). I don't know if the groundwater pump introduces to many nutrients as it flows though a waterfall feature (last pic).

This pond is already over 10 years old so I guess the setup kinda works but it doesn't seem very nice for the fish in my opinion. Maybe I'm wrong. What do you think?