Ideas: visit the premier koi pond and/or garden centers in your area. Talk to their owners about your set up. Take along a few single-page posters showing your house, the real estate listing number, and a few beauty-shots of your koi and pond. Also use social media to find any koi or garden pond enthusiast groups in your area, to let them know of an upcoming opportunity too.

For house showings, print lots of pictures showing your koi and your pond at its best. Leave them on a table or counter, along with a short write up of your pond maintenance routine. Any water garden requires some care, so let a prospective buyer know that it's not rocket science and for a little work they can reap a large reward.

Then, be prepared to walk away and not look back, because once it belongs to someone else it's out of your control. All you can do is attempt to connect with a caring new owner. Good luck!

There will be potential buyers who will find the pond a plus and others who will find it a minus. Just like other home features that reflect an owner's personal preferences or hobbies.

We bought a house with a koi pond (MUCH smaller, though) and we thought it was a plus. When we realized that the upkeep did not appeal to us, we filled it in. So, I would say that the presence of the pond was not a deal-breaker, but an appealing feature at the time we looked at the house.

I like koi ponds, but most buyers have no idea about them and what's required to maintain them. I also suspect that most would not see it as adding value. It's like a swimming pool: some people like them, but others see them as a nuisance and a negative. If you're lucky, buyers will see it neutrally. Do not expect this to be a selling point.

@Vadim Goldstein It would help if you posted some photos that show the scale of the pond and the interior architecture around it.

I'm not into fish, so it would not be a plus for me. Why not investigate the cost to fill it in, so if a potential buyer, like me, loves your house but hates the pond, you could offer to do it.

Don't base your advertising the house on that pond. You would be reaching out to a very, very, small number of buyers.

No insult intended Vadim - but I’m repulsed by koi ponds and the potential house would have to be pretty darn perfect otherwise to make me interested. I’d not advertise this as a plus. I do wish you well!