Swordtails very skinny after having fry? parasite?

[Marne]

I bought some swordtails a few months ago (a couple females and a couple mails), one gave birth within a week and the other gave birth a few weeks ago, both females have gone really skinny, have not conceived again and they don't look very happy .

Does this happen after giving birth? or have they got some kind of parasite? all my other fish seem ok and my water is perfect (tested yesterday).

They might just need feeding up a bit, have to tried separating them and offering high calorie live food? I had some guppies that had been almost bred to death by their previous owner and they really struggled at first in a community tank. Popped them in a small, very well filtered quarantine tank for a few weeks and fed live and flake food and they soon put back on their condition.
If they do have parasites then anything else in your tank is also at risk so maybe look at dosing the tank, hopefully someone with a bit more experience of parasites will pop along soon to advise you.
Best of luck with them.

Thanks Mogz, it only seems to be effecting the 2 sword tails which have given birth and one of my mollies who also gave birth a couple weeks ago, I havn't got another tank so can't separate them but I will increase their food a little, they get flake, pellets, cucumber and algae wafers ( they are for my plecs but all the other fish seem to like them too), I'm feeding once a day and they all seem to be feeding ok.