Any Input On My New Guppies?

Hey everyone! I am so new to this that I am hoping to get some advice from some experienced people. I received a small 5 gal acrylic aquarium for Christmas from hubby. Set it all up with gravel, etc. on 12/26 and did a (very) little bit of reading. Went to PetCO (have since read this was possibly the worst place we could have went) this past Sunday and purchased 5 pretty guppies from a tank labeled as all male. Now as I am learning more I am wondering if my fish are going to be okay, also wondering if ones of my "boys" just might be a girl and pregnant. It appears to be much more "pot bellied" than the other four. They all seam to be doing really well despite my inexperience but I was just hoping for some input. Thanks everyone. Candi

The males have a "gonopodium", this is the breading organ that allows the male to breed with the females.


(male guppy)

See the fin nr the bum of the fish it's pointed and the males are able to move it around.




(female platy)

See the same fin on this fish is triangular, this indercates it's a female, and this is the same process with all the common livebearers.

I would also add that on Mollies, I have seen that they like to collapse their fins once in a while, making the females fins look more like a male. Just watch for a while and you will figure it out. I haven't seen this much in other fish, but it may occur too.