Kale for Koi?

[ZEROPILOT]

My $6 koi quickly ate three, $45 water lilies not long after I set up my pond and have continued to demolish and devour any other plant that they've ever been introduced to.
A while ago and without asking here, I began to toss some Kale into the pond. Not regularly, but every now and then. Because I also keep tortoises. And it's part of their diet as well.
My question is: Have I overlooked something? Is kale o.k. to feed to koi?
Thank you for your thoughts.

 

[MitchM]

Kale is ok.
Any leafy green that we eat is ok.

 

[mrsclem]

Mine love romaine lettuce. Try watermelon, another treat!

 

[ZEROPILOT]

I wonder about hibiscus leaves now.
I've got them all over the yard. Its a staple food for my tortoises.