Feeding koi Duckweed
Producing your own duckweed has got to be a plus, for anybody keeping koi. I will admit for me it may be much easier having a warm climate all year round. It is a rather satisfying endeavor producing and feeding food from your own system.
Its a good idea to keep this as small as possible, it can quickly out grow you and become a burden.
I feed about 2-3 hand fulls a week, its all gone by the next morning.
The benefits are: it takes out a lot of nutrients out of the water, if the growth slows down its telling you the plants are struggling for food so it,s a good indicator of nutrient levels. I grow duckweed in a separate tank with no fish except for small barbs to provide the poo.