I have an outside pond with 2 koi & 23 large goldfidh. Every year the fish spawn in the spring.?

Question

This was the first time in 30 yrs.they did not spawn, can anyone tell me why? I live in San Jose Calif.

Answer 1

After 30 years, they may be too old.

Under normal pond conditions, indiscriminate and spontaneous spawning may occur, unobserved by the pond owner, and the resulting eggs either are eaten by the adults or disappear down the overflow, particularly when the pond is free of vegetation.

Koi need not spawn in order to remain healthy. On the contrary, the process has accompanying dangers to health, color, and patterning of fish which are involved.

Answer 2

Its possible the conditions just didn't please them this year. You could try doing a partial water change and they might breed now, but don't wait long of it will be wait too late in the season. Sometimes the fresh cool water followed by a nice warm day will initiate spawning. Every year my moms fish spawn right after she does the yearly clean out and fills with fresh water.