| The differences between male and female koi |
| The differences between male and female koi The differences between the sexes become more apparent as they age, particularly so in the spawning season. Male koi are slender, compact and torpedo-like in appearance, with very trim lines and smooth body contours. They also show behavior that is particular to male koi and is particularly noticeable when all male koi are segregated into a single tank. Male koi tend to dart around energetically, with sharp turns of speed, showing real 'attitude' and a skittish character. They are less trusting than the opposite sex and this shy temperament is all the more apparent at feeding time when they will take considerably longer than females to feed at the surface. The key distinguishing physical feature that male koi possess develop in late spring as they come into breeding condition. Often mistaken for white spot, breeding tubercles appear on the head, flanks and tail of mature male brood fish. To the touch, these tubercles make the typically slippery koi feel 'as |


| rough as sand paper' giving them better purchase for when they drive and push against gravid females in an attempt to expel their eggs. In darker koi, white tubercles will be clearly visible but on paler or metallic koi, tubercles may only be evident to the touch. Females on the other hand, do not develop tubercles nor will they retain the sleek lines of a male as the breeding season approaches. Eggs that develop in the ovaries will swell, leading to an increase in volume to the abdomen. In addition, female koi tend to behave in a less timid manner to a tank full of males, feeding voraciously as soon as the food hits the water. Whether these characteristics are as well defined and identifiable in a pond of mixed koi is debatable, but males are still less likely to be the first to feed of the surface. |
| When the water temperature is 60 degrees or above males create sperm . Which can be observed by applying finger and thumb either side of the vent. A female will show a swollen abdomen and a pink and fleshy protruding vent. Koi......Ornamental and great for algae control. These are one of the most beautiful fish. They come in various bright colors. As a result they can always be seen in your pond. They grow up to 24 inches. These fish are great algae eaters. |
| The easy and inexpensive way to winterize a KOI pond |