Koi and plants

Koi will eat all sorts of plants but there are a few that they like more than others. The best way I found to keep some plants alive is to feed them a steady diet of their favorites. Mine would devour lettuce, elodea, duckweed or any other soft tissued plant. Especially when they are young and always hungry it's a good idea to keep their bellies full. As they mature and get larger they might not bother the plant's as much.

As for your plans for future ponds, if you want to connect them you need to look at 15-18" diameters or larger for the tunnels. It might be easier to do a trench and bridge setup than trying to use a round tube/culvert. I've seen 30" female koi that were 10"+ in diameter.
 
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