Hi people, peace and blessings to all!

I was looking for a forum to join because I have seen the beauty of these magnificient fish from our Creator.

I have moved into a seperate entrance and the owner of the house has offered me to use her pond as she has nothing in there at the moment. Only reason she has no fish is because she's old and has no time to look after koi, she says they can become a handful.

I'm not familiar with the setup but I will take pics later. the property uses borehole water so I will use the same for the pond. The filtration system looks like a pool filter, and a large filtration can on the side. The pond itself is quite big with an overflow tank on the side.

My one friend has been breeding so he is familiar with koi and he will advise me what to do, however, one man's knowledge is never enough to reap the full benefit of anything that is why I joined this forum to learn more.

So...

The very first thing is, if the system has been standing for quite some time, not really used only to drain out water in winter season, how do I check if everything is still working fine?

The other question is, when using borehole water, what challenges do I face to treat the water before I place fish in them?

Please advise!

Darling post some pictures of the pond and filters