I have kept 3 Swordtails with a breeding pair of German Blue Rams for about 3 months and now there are probably 50-60 fry. I have 2 females and a 1 male. The male is not aggressive at all and just occasionally bothers the females, but never really harms them physically. You will know the fry are coming when you there is a very visible light black dot which are actually the eye of the fry. I have Guppy Weed in the tank, but I always collect the fry with a small net and put them in a breeding box due to the lack of a fry tank. Fatten up the female with protein rich foods, I use frozen bloodworms. You should prepare fry food. I like to use newly hatched brine shrimp along with anything with algae on it. If I have some floating plants (usually frogbit) with algae growing on the roots, I just place it in the breeder box and after a day or two, the roots are clean and algae free. The algae provides digestive support and also varies their diet for healthy fry. When they get big enough I feed them crushed pellets along with the brine shrimp and let them out of the breeder box to swim with the adults. I would recommend getting a fry tank, but you will survive without one.
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