Oh no, one platy down, another not looking good.

[WILDER]

If you have just added the med to the tank that can irratate them for a while.

 

[sylvia]

I don't think danios have barbels - or at least you can't normaly see them.
I don't think plecos like salt.
Your platy with the strange scales may also have dropsy which is caused by internal bacteria. Most of the symptoms are caused by internal bacteria in fact.
I would go by a small heater and move the pleco into a spare bucket. Then treat the main tank with salt, raise the temperature to around 80 deg F and treat for internal bacterial infections. Plecos don't often catch diseases for some reason but you may want to treat it for internal bacteria too - don't add salt.
Your new fish were probably carrying some kind of disease.
Don't keep fish bagged - they'll die.
I think a lot of that was already mentioned but never mind.

 

[Talisman]

the platy died.

thats 2 in two days.

yeah ill have to get another tank, i was thinking about it already, now i think its a must.

bummer

 

[WILDER]

Sorry for your loss.

 

[Talisman]

thanks wilder. guess its a learning curve. just a sad one