My sister's panda platy sick - now in my care

[BananaBean]

So, my 10yr old sister got 3 panda platys from Petco last weekend (I know it's horrible, but she was SUPER impatient), no research, nothing. Now, two of the platys have died and the final one is in my care. It's swimming near the surface and a bit lethargic, but not much. I have a well established goldfish tank that I put breeding boxes in (I accedentally bred zebra danios, I have 6 fry), so I put another breeder box in there. It has no holes in the bottom, so the platy water isn't mixing with the goldfish or danio water.

I've researched their care, but does anyone have any tips?

 

[carsonsgjs]

Is the platy in the breeder box in the goldfish tank now? If there’s no holes in it allowing water to pass through and circulate then the platy is basically in the equivalent of an unfiltered uncycled box, allowing waste to build up. That won’t be helping the platy.

 

[BananaBean]

Is the platy in the breeder box in the goldfish tank now? If there’s no holes in it allowing water to pass through and circulate then the platy is basically in the equivalent of an unfiltered uncycled box, allowing waste to build up. That won’t be helping the platy.

Welp, suppose I'll have to do that. Was planning to change it every day, but I can see how that would be annoying.