platy has pink thing on her butt!

I am guessing you want to ensure your platies strictly breed with one another? If that is the case, simply keeping platies without swords is how to accomplish this.
 
In order to breed these fish properly you should select some breeding stock with all the desired qualities you are after. Also the prospective parents should be in their prime and not old fish or very young adults. The pair should be placed in their own 24 x 12 x 12 aquarium with a mature sponge filter and lots of live plants especially on the surface, (Indian Fern is good for this).

The sexes should be kept apart by means of a tank divider and fed with lots of good conditioning food either live, frozen, or freeze-dried. The temperature should be between 76 to 80°F, the pregnancy will be shorter at the higher temp and the resulting fry will also be more vigorous. Once the pair look to be in peak condition remove the divider, they will begin mating almost immediately, although it isn't strictly necessary to do all this, by doing so you will be ensuring that the brood will have a far better chance of being large and healthy.

The pregnancy will last from 4 to 6 weeks depending on the temperature and the brood size will be up to as many as 80. Unlike many other live bearers Platies are unlikely to eat their own fry especially with a lot of plant cover available. But to minimise the risk the male should be removed after a couple of weeks and the female once she has given birth.

The fry are very easy to raise and will accept crushed flake right away, but better growth rates will be achieved if you go to the trouble of using newly hatched brine shrimps for their first food. As the fry grow they will need regular water changes in order to maintain good growth and eventually they will need moving into larger quarters. Between 8 to 12 weeks the fry should be big enough to sell.

(Taken from the good fokes at http://groups.msn.com/Breedingtropicalfish/platies.msnw)
 
ok, 1, i dont have anymore room 4 another tank, and i wanna buy live brine shrimp. i have a little net for keeping other fish in the tank but seperate, can i put them both in there til they breed?
 
mr.amateur45 said:
ok, 1, i dont have anymore room 4 another tank, and i wanna buy live brine shrimp. i have a little net for keeping other fish in the tank but seperate, can i put them both in there til they breed?
You can try, but oftentmies these nets stress fish out severely so it may be counterproductive. Really, livebearers do fine in tanks without all the trouble. They breed like crazy. They can also store sperm for months at a time, so she is likely already near pregnant again. If you want to ensure a certain pair breed then you pretty much need another tank, otherwise nature will pick for you and you just deal with the results.
 
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