Platy Problem

[Pysgodyn]

I have a four month (ish) old blue platy - over the last few days she's been very still and sortof hovering over the gravel (and mostly hiding in a cave). She just keeps flapping her pectoral fins. She did come up for food, so it's not a case that she can't swim around, she just doesn't (if you know what I mean!).

I have successfully bred livebearers in the past, and she doesn't look pregnant.

I did have an aggressive gourami who took a bite out of her tail a few months ago (I've since removed it), and I can't see any further difference in the nipped tail (so I'm assuming this is nothing to do with whatever the current problem is).

The water quality's fine.

Any suggestions of cause and/or solution? Many thanks

 

[Duck and Dive]

Im not 100% sure but she may be stressed, how is the water quality?

 

[Pysgodyn]

Like I said. Water quality's fine.
Ammonia = 0
Nitrite = 0
Nitrates = very very low
Long established tank with plants.

 

[Duck and Dive]

Oh yeah, sorry missed that part. One of mine had the same problem but didn't make it. Not saying yours will die, I think it might be a wait an see what happens situation.

 

[OldMan47]

Forget the usual parameters. Do you have a KH and GH reading on that tank? The mollies and platies will both do much better at high water hardness readings and pH above 7.5.

 

[Pysgodyn]

Dead!