comments on what may have happened please

[mousey]

Ok bought a virginal female guppy- red tail gold. Tried to get the old male to mate with her but he wouldn't.
Bought a young gold male- enthusiastic about his job-- fish pregnant but not very big.Eyes seen in gravid spot.Seemed healthy enough but found listless at the top of the tank one evening. Water parameters 0 ammonia and 0 nitrites. tanks is cleaned bi weekly but not that week.
placed in breeder tank thinking she may have 1-2 fry. Found dead next morning.
had added a male betta the week before also but he did not seem particularly aggressive and I have kept bettas and guppies together before.
No marks on guppy just dead.
Next day found my 1 year old platy dead. No marks on her. Healthy and swimming about the day before.
Male guppy was ok.Betta ok.
Thoughts:Female guppy died in labour,initially until I found the dead platy. So did betta kill both or is male guppy carrying a virus?
Anyway gold guppy removed to another tank so as not to harass the remaining grey female.
Also had added the older female grey guppy into the mix.( my guppies are few now) She has never been bred before and gold male was happy. Tummy was getting larger but not gravid spot, so I don't know if she was pregnant or not.
Male betta is contained just in case he is aggressive. Female guppy noted to be short of breathe yeasterday and hiding. had a slight difference in her coloration in a small area on her flank.
Also had to collapse another tank and shuffled some other fish about. Added to her tank a total of one platy and 1 Small 3 inch CAe. This morning the guppy was dead. Ammonia .05, nitrite 4ppm!!Water change 2 days ago 20 %.
peviously the sisters to the grey guppy had a reovirus and died of either kidney, or liver failure or dropsy- 4 girls died 4 different ways Approx 8 months ago.
I suspect that this girl had kidney failure exacerbated by the sudden elevation in nitrites that due to age and previous exposure to virus may have triggered her into something else.
however if the betta did not kill the platy, did the new male guppy bring in a virus that has caused the problems.
Sorry it seems so complicated but I am not used to fish dying on me other than old age.
So to recap is there a fast moving disease brought in by the new male guppy that also affects the platys.?Fish are healthy and eating today- dead by tomorrow.

[Louise163]

I would look into camallanous worms which livebearers are prone too.
Long stringy white poo or clear mucas poo.
Being thin or bloated.
Enlarged anus or red inflamed anus.
Worms hanging out the anus.

Bacterial infections signs with no symtoms, being pale or darker in colour. listless and lethagic and not eating.

[mousey]

really had none of those symptoms. healthy until a couple hours before death.poo "normal" for guppy that eats lots of greens.

[TheOldSalt]

It's a puzzler, but my bet is on the new guppy. Lots of nasty guppy diseases sweep the world every now and then, and some of them are easily as bad as this. Luckily they tend to vanish soon after they appear. Your best bet, really, is to try to get your guppies from a guppy breeder instead of from a store, and to keep them all separated as much as possible for awhile until you are sure they're safe. Put your new fry into yet another tank set up JUST FOR them, and soon you'll have your own colony of perfectly clean ones that you can ise as your beginning broodstock for your breeding program.

Getting guppies from a store is, I hate to say it, a very risky proposition much of the time. The stores take what they can get and what they can get tends to not be very good.

[mousey]

Thanks. All is quiet in the tanks just now.