Help on pond project

[pacu22]

My father is opening up a new restaurant and it has a pond on the outside. He is asking me to put together some ideas on what to do with it.

Few things you should know:
1. it is not covered
2. it will not be heated
3. it is outdoors in Socal weather
4. it receives little to no direct sunlight throughout the day
5. no budget, but the cheaper the better
6. there are two circulating pumps, but I am unaware of the gph and so on

Description:
I have not measured the exact dimensions, but it is approximately 35 ft long and 3 ft wide, with a depth of no more than 12 inches. Towards the middle of the pond is a bridge/walkway to enter the front doors of the restaurant, I estimate it to be about 10 ft long and the water flows under it. I would like to change the substrate, but that would cost more (unless it is something cheap)(maybe bare would look good?).

Here is a sketch I drew of the shape (note: the dimensions are estimated).
The other pictures were taken on my phone, they start from the left and go from end to end. The last picture is of the substrate and some of the plants currently in the pond.

Any ideas?

 

[Muske]

No Koi...

A couple of Bullheads and a few Goldies would look nice. Those filters are little more than a power with a pre-filter. The plants look like they could be repotted. If they are growing well enough, you can try other plants for a little extra filtration and diversity.

 

[pacu22]

No Koi...

A couple of Bullheads and a few Goldies would look nice. Those filters are little more than a power with a pre-filter. The plants look like they could be repotted. If they are growing well enough, you can try other plants for a little extra filtration and diversity.

So minimal amount of work, just add fish? What are some good plants?