Over Sized Guppies?

[KLF]

I have always (15+years) had/bred fancy guppies. Never anything special, pretty much the same line the whole time, mature females about 1". I started with a 10g tank, then 20, and now I have a 50g. I moved and my sister 'took care' of my tank for about a year until I had time to take them back - she bought a Koi who ate all my guppies..
I went to PetLand (they had a 50% off fish sale) to get some more guppies and they had the biggest guppies I have ever seen! I bought 5 females ranging from 2" - 3" and they look 'fat' (not unhealthy, just big) and 3 males, one is normal size, one is a bit bigger, and one is 2"!!
I have tried to search for information on factors determining adult size, I can't find much. Some seems to be genetic, some is tank size, some is dependent on how early in her life a female gets pregnant, but I can't see how those (except genetics..) would give a 1" guppy the potential to be 3"... So bizarre!
Is there a "giant" strain? Is is a mutation? Is it truly just because they grew up in a huge tank full of females and were never bred? I read one post somewhere from a year or so ago (don't remember if it was on this forum or another) about someone in the States who had seen similar "Jumbo Guppies" at a PetLand in their area. I went to the Regent PetLand in Winnipeg, MB, Canada.

Any info, links, etc would be much appreciated!!!!!

-Karina

 

[Ludwig Venter]

Talking of oversized guppies....... I think this is a bit extreme..... Fake Photo???

 

[KittyKat]

2" (without tail) to 3" (with tail) is standard size for well cared and mature fancy females, fancy males are often 1-1.5" without tail, 2-2.5" with tail; mine have always reached that.

The other thing is that farmed guppies are sometimes given growth hormones, so that's probably why the ones at the shop are that big.

 

[Athena]

I once had a female guppy that grew to 2 and a half inches and one of her female fry also grew to be just as large - they also outlived all the other smaller guppies, for some reason.

I don't think females grow that large due to never breeding since my gal obviously did breed and was still a bit of a giant.

I always wondered why they were different to my other guppies...still don't know the reason.

I haven't kept guppies for a few years so not sure if it's a common thing or not these days.

Athena