my koi keep digging up my plants

[The GEMRS Baby!]

any suggestions of how to keep my plants in the rocks? they're not digging them up to eat them or anything. they just dig them up with picking up stones off the bottom after i feed them.

[oscarbartoni]

Are the koi n a pond or an aquarium and how large are they? They should be in a pond or an extremely large aquarium. In aquariums with cichlids (which also dig) I have put my plants in margarine containers (make sure to clean them out first) and put first some good garden soil in the bottom, followed by aquarium gravel. I cut a big "X" in the top that I will push the roots of the plants through and then plant the roots in the gravel and snap the top on. You can hid this behind rocks or even before you plant it, you can rub some silicone on the outside and then rub that in aquarium gravel. Let cure and then you can plant as I described.
In a pond I would put some chicken wire over the tops of the pots to discourage the digging of the points. Or even larger ricks (big enough so that the koi cannot move them ) around the plants