Swordtail age

Question
I have only had my aquarium for about a month and when i got it, my uncle, the local fish guru, gave me some equiptment to breed swordtails. I have visited many other sites to try and determine the age and probability of my fish being pregnant. My tank is 20 gallons and i have 5 female and 1 male swordtails in it. I have a mat that is on the base of the tank that will apparently let the young avoid being eaten. Are my fish pregnant if they have a dark area at the base of their tail? How old are they if they are about three centimeters?

Answer
Hi Brayden,
 There is no way to age swordtails that I know of.  That said, a swordtail that is about 3 cm long is large enough to breed.  Give them time, keep their water clean and they will breed eventually.  

-- Ron
  rcoleman@cichlidresearch.com
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