4 A 5 cm grass fry can have at least six to seven per catty, so it is normal to have six to seven per catty because of its light weight, but the survival rate of grass fry is very high, and they can grow to three to five catties in a year or so. In addition, the profit value of grass carp is very high, with an average of 25 to 25 kilograms in 30 yuan. It can be said that raising grass carp is very profitable.