Guys I'm thinking about adding some plants to my 117 gallons koi pond, but quite confused what I have to choose. I found this article https://www.divesanddollar.com/koi-pond-plants/ and convinced to choose between lily or iris. Can someone give me some advice?
If it were my pond (and it isn't) I would not put any plants in it, because I would want to admire the fish for their colours, not get distracted by plants. But as you have asked which plants should you have "lily or iris" if you can not decide then don't. Why not have both? (But do take heed of the advice given in the link)
Good quality costs. Bear this in mind before you start.
Sorry if my reply is NOT want you want to hear, but what I have said is true.