The winter of 2009 we lost a lot of fish to bitter cold, including one large koi. Since we lost that koi, we've not had any baby koi so I assume the three I have left are all the same gender. (They produced babies in the past and are over 12 inches long so they are mature.) I have read numerous web sites about sexxing your koi but I cannot tell whether I have all males or all females.

My question is, if I have females and no males, will they still produce eggs or do they only produce eggs if there are males around to fertilize them? If females get fat with eggs each spring regardless, then I doubt mine are females since they don't seem to get bulgy. But if they only get fat with eggs if males are around, then mine might be females.

I was told that if I got some water from a pond that had females in it and poured it into my pond, I could tell the gender of my koi from the reaction--no reaction, I have females and frantic reaction, I have males. Trouble is, we have few knowledgeable koi dealers around here.

Thanks.