How to choose koi? These purchasing tips you need to master

1. How to choose koi.

The selection of koi can follow certain standards. Since ancient times, the judging standard for koi has always used a 100-point system: conformation 50 points, color 30 points, pattern 20 points. Recently it has developed into the 3-2-2-1-1-1 system: conformation 30 points, color 20 points, pattern 20 points, quality 10 points, taste 10 points, style 10 points. Among these, conformation includes swimming posture and body shape, with genetic factors playing the dominant role; for beautiful color and pattern, the koi's own quality accounts for 70%, water quality 20%, and feed 10%. Therefore, improving water quality is especially important for enhancing koi coloration. So-called excellent water quality means a pH value of 7.2-7.4, low content of iron ions, chloride ions, sulfate ions, etc., low hardness, and abundant dissolved oxygen, while the feed is rich in color-enhancing substances such as spirulina, Antarctic krill, alfalfa meal, Acetes shrimp, dried small shrimp, or artificial pigments.

2. How to distinguish male from female koi.

The female fish has a larger abdomen than the male; at the anal opening, the female is wide, flat and nearly round, while the male is smaller and elongated oval; when reaching sexual maturity, the male has rough keratinous protrusions called "breeding stars" on the fin rays at the edge of the pectoral fins.