Platy Dead at 5 Days

[ETNsilverstar]

So we got some new fish on Saturday for our 10 gallon tank. After much debate and "no, that's too big for our tank" the kid decided on some platys. She picked out 4 (3 adult and 1 baby) and they seemed to acclimate just fine. But today (Wednesday) I saw one was just chilling at the top of the tank not moving much. I pulled it out into a small fish bowl to see if I could save it, but it was already sinking and not visibly breathing (though it would dart around every few minutes before sinking to the bottom again) and died shortly after. There wasn't really anything notable about its condition either...no frayed fins, no spots or visible parasites, no bloating, no red gills...aside from the swimming issues it looks just like the other one. I'm hoping someone might have some ideas so I can keep an eye on the others for signs of something, but for now they seem fine.

Tank is cycled, parameters were 0, 0, ~40 right after I pulled out the fish, but I did a water change right away and haven't checked again (though nitrates should be around 20 based on the water change). Other inhabitants are a single oto (others died forever ago) and a bunch of ramshorn snails.

The way it was acting makes me think it was just stressed from moving to a new home, but it's strange that it took 5 days to happen.

 

[Ghelfaire]

It may have been a few things.
1. you added too many fish at once and the weaker one didn't make it.
Or
2. Your male to female ratio was off and she was pestered by the males to death with them trying to mate (not necessarily nipping just exhaustion)

 

[ETNsilverstar]

It may have been a few things.
1. you added too many fish at once and the weaker one didn't make it.
Or
2. Your male to female ratio was off and she was pestered by the males to death with them trying to mate (not necessarily nipping just exhaustion)

I guess it's possible that it was too many at once, but I already had a fully established cycle, so that seems strange to me. Anything is possible though.

I knew I was forgetting to mention something...they were all female, so not a ratio issue.

 

[Hobbyist]

So we got some new fish on Saturday for our 10 gallon tank. After much debate and "no, that's too big for our tank" the kid decided on some platys. She picked out 4 (3 adult and 1 baby) and they seemed to acclimate just fine. But today (Wednesday) I saw one was just chilling at the top of the tank not moving much. I pulled it out into a small fish bowl to see if I could save it, but it was already sinking and not visibly breathing (though it would dart around every few minutes before sinking to the bottom again) and died shortly after. There wasn't really anything notable about its condition either...no frayed fins, no spots or visible parasites, no bloating, no red gills...aside from the swimming issues it looks just like the other one. I'm hoping someone might have some ideas so I can keep an eye on the others for signs of something, but for now they seem fine.

Tank is cycled, parameters were 0, 0, ~40 right after I pulled out the fish, but I did a water change right away and haven't checked again (though nitrates should be around 20 based on the water change). Other inhabitants are a single oto (others died forever ago) and a bunch of ramshorn snails.

The way it was acting makes me think it was just stressed from moving to a new home, but it's strange that it took 5 days to happen.

If I may ask, what's your tank temperature and how did you acclimate them and how long did you acclimate them, also did you watch “closely” the other fish in the tank if someone is dead or sick.

I

If I may ask, what's your tank temperature and how did you acclimate them and how long did you acclimate them, also did you watch “closely” the other fish in the tank if someone is dead or sick.

I mean in the tank you bought the fish from In the store

 

[ETNsilverstar]

If I may ask, what's your tank temperature and how did you acclimate them and how long did you acclimate them, also did you watch “closely” the other fish in the tank if someone is dead or sick.

I

I mean in the tank you bought the fish from In the store

Temp is 74, drip acclimated for about an hour. As to the tank at the store, they were the only ones left in the tank and I didn't see any dead ones or anything.