With artificial breeding of carp, fry of silver carp and grass carp are launched into ponds. For what purpose is this done, despite the fact that these species (silver carp and grass carp) are not economically profitable?
1) ponds overgrow very quickly, which disrupts the growth and development of carp;
2) silver carp and grass carp are herbivorous fish, they destroy vegetation, cleanse ponds.
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