Fat Zodiac Loach
 

I've had 3 zodiac loaches for about a month now. All seems to be well with them- they have a big den and keep to themselves. I haven't really seen any signs of aggression. One of the loaches has gotten quite plump, but the other 2 are slender. They were all the same size when I purchased them.

I know that it's unusual for loaches to breed in regular tanks, so could this difference in girth be a gender thing? What are the chances that I do have a gravid loach?

Sorry, no pic... I can never get them to stop and say cheese :(