refurbishing a pond

[speakerpedal]

as I kid my father kept a pond in our backyard. After coming home from school, I noticed my dad has decided to start fixing the pond up from it's fallen years.
What steps should he take to putting the aquarium back together.
The water now is relatively murky. We have a bunch of feeders and koi living in there but as far as sprucing it up what should we do? there are a few plants growing but that's really it.

[Ty]

That is what I have been doing at work all this week.

It was a old concrete pond, and we reset most of the rocks around the pond, and clean it up nice. then we added fresh topsoil, and lots of new plants. We also drained the pond untill we finished, then cleaned it, and refilled. Tomorrow we are going to add some mulch and new koi to it.

[speakerpedal]

I'm beginning to think this refurbishment is going to take a huge chunk out of my summer.