esshup, we are getting about 80-85% confirmed at 8-10". If they can't be sexed by 12" early Feb, they get culled.
On 11"+ you can confirm about 75% of the females by October.
No pellets, these are all conditioned on Koi from 4"+, for example, fish are gathered in late Sept at 4-6" and moved inside and kept at 50 degs through winter with a fair amount of Koi. April 1st they go back outside in 4 ac grow outs full of fresh Koi and then are collected again in late Sept at 8-10". Anything above average is desired but if it can't be sexed, it's removed. Most of the 8-10" fish can be sexed and that same 80-85% will spawn in tank when temps are brought up in Feb.
To see the best genetics, the shooters during the next period outdoors are separated the following year for the best brood stock.
Then the goal is best growth of the offspring but they still need to produce stock for reproduction to choose from so it's 2 years before the shooters are separated.
Yes, we are talking about 2 different goals here, but if fast growing fish are a part of the target for trophy potential, those that don't mature need to be removed completely.
The difference is those shooters that appear from the 8-10-12" fish are the one's we want for breeders for stock to raise and sex for trophy ponds. My point??? If you can't sex them until 14-15", the potential to grow a trophy is not good.
I also think there is a misunderstanding on the sexing process because seldom do we see sperm, only egg but we can have extra females without issue-until we need to eliminate the male from the equation, then we get in trouble assuming it's a male because we didn't get any egg. 75% of males you won't see sperm, if you do, it's a bonus indicator but not the norm.
Keep in mind, these are fish that are observed every day to confirm males on nests that can be pit tagged at that point. There are 2 categories..female and unsure, which brings me to another point for Cody, another reason for glass vs plastic is sperm will show on the end of glass that will not show on plastic which removes fish from the "unsure category" but not many.