Guppy not getting pregnant anymore

[FreedomLantern]

Hi!
I bought a breeding pair of Red Deltas from Aquatic Warehouse and I put them in a 3 gallon tank along with two other mixed females. From the very beginning, the male was super interested in the mixed females and didn't pay much attention to the Red Delta female. Well, anyway, she did give birth twice to roundabout 20 fry each time, but then for a month now she doesn't appear to be getting pregnant at all. The male is showing zero interest now and she is skinny (but still shows a gravid spot). The other two mixed guppies gave birth to 55 and 19 fry respectively, so clearly they're getting pregnant. What could be going on?! Here are pictures of the male and female in question. I am feeding them Tetra tropical color flakes.
Thank you!

[SaraB]

I had something similar with my platys. I had 1 male 3 females but he would only chase the 1 female. I think male livebearers might just have preferences.
Your female could have just been holding sperm from a male from the store and given birth via that since yours isn't interested in her.

[FreedomLantern]

So should I remove the other females? I'm interested in breeding these to sell.

[SaraB]

Never keep a single male livebearer with a single female. I would sell the other 2 females and buy more of the females of the color you wanted. Also do you have a separate tank for the fry to grow in? 3 gallons is going to get overstocked really quickly.

[FreedomLantern]

Yes, I have a 45 gallon and a 20 up right now, plus others that can be set up if necessary. I'll look into it, Aquatic Warehouse was selling them as a special and only in pairs. Can I remove the other two females and then bring them back within a couple days? I don't have to sell these, they're really productive and I'd rather keep them, but I can move them.

[FreedomLantern]

The fry don't stay in the 3 gallon, that's just for breeding. Also, do you have any tips on how to grow them out faster?

[SaraB]

Live foods tend to grow my ry a bit faster. Try daphnia or something else that is small enough for them to eat.
Again i'm not sure i'd trust a single male with a single female but you can try it for a day, if you see him beating up on her then add the other females back in.

[FreedomLantern]

Okay! I'll definitely try that (I have mosquito larvae, so that should work). Yeah, I know that if it's 1:1 that's a bad thing. I'll only do it for a day though, just to see if that'll get her pregnant.
Thanks!

[FreedomLantern]

Okay, took out the other females and the male is still showing zero interest in her. I guess I'll have to buy more, but then I need to figure out what to do with the extra males since they only sell them in pairs...

[SaraB]

If you are breeding to sell then just sell the extra males. Or sell this male and see I'd you have better luck with another male wanting to breed.

[FreedomLantern]

Okay! Thanks for your advice.

[BigNorsk]

Looks like so called livebearer disease which is from parasites.

Run them through a general cure or prazi pro treatment.