Sunday, 4 May 2014

Sexing ranchu goldfish, very difficult indeed.

We have had an interesting revelation in the last few days. Last week, i decided to isolate one of my ranchu that had developed an ulcer over the winter. I wasnt entirely happy with how it had healed and wanted to give the fish more time in cleaner water to see if it would improve further. It had also seemed unwell, isolating itself and not showing much energy.

After a few days of very limited feeding and massive daily water changes the ranchus energy levels were back to normal.

Due to heater shortages, time and space etc, i decided to move all the fish, using the two smaller tubs, putting them all through the same conditions. The ranchu are all really enjoying the cleaner conditions and the sexes of the ranchu seem to have vecome clearer. Im well aware that its very difficult to sex goldfish accurately, and ranchu particularly, due to their generations of in-breeding which can make identification very hard, breeding tubercles for example are common on both males and females in my line, though more prominent on the males.

Last year, when chasing was observed, i had identified what i believed to be 3 females and 3 males. The males had all released milt at times, the suspected females were generally the fish being chased, and they also had what i considered to be female protuding anal vents and had never released milt. 

However, on moving the ranchu today i have seen what i believe to be milt, from two of the "female" fish with what i considered protruding vents. This discovery has meant that the ranchu below could be the only female in my group.

Unfortunately, given the observed milt, tubercles on all fish, chasing but no eggs, a group of only males might make sense. Another shopping trip may be in order....