Dropsy In Female Guppy

Hi, first post (most unfortunately on this topic).

I have an 8g tank with 5 adult guppies (3 female, 2 male) and quite a few fry, one live plant on driftwood, 2 fake plants. Parameters are fine, I feed twice daily and did a 25% water change only a few days ago.

All my guppies seem to be healthy except one female. She has already given birth to quite a few fry (she was pregnant when I got her about 2 months ago) and up until yesterday was looking fine and acting pretty normal - she just tended to stay among the leaves quite a bit (but I think that was mainly for birthing and peace reasons, as she'd been doing it for ages). Then this morning, I went to feed them and check them before work (I feed and check twice a day - mornings and evenings) and she was quite bloated and somewhat pineconed, but otherwise acting perfectly normal. She had not been in any way bloated last night. I came back from work this evening and she was almost vertical (head facing down) in the tank, unable to stay submerged without effort. Her scales were showing greater signs of pineconing and she was rather listless with tail not fanning out (although she did have bouts of activity).

Anyway, here is a photo of her that I took this evening (she looks better here than she does now):



My question is, could dropsy happen this quickly? And am I right in keeping her in a breeding trap (I don't have a second heater and it's winter here, so the water will get too cold) to prevent the other fish from eating her if she dies overnight or while I'm away?

My main concern is, if I can't cure her and she dies, I don't want the others getting it too.

It looks to me like she is ready to drop a bunch of fry. . I would leave her in the breeding trap for awhile longer, is it possible she is like that becuase she is giving birth. ?

Are you sure it was this guppy that gave birth.

She's been giving birth for a little while now, hence about 15 little fry in the tank (the others aren't at advanced stages of pregnancy yet).

Currently she's in the breeding trap (something I don't actually use for breeding, because it seems to stress them out way too much - I plant extra plants when I want fry to survive) and she's just hanging by the tail from the surface, drifting, laboured breathing with scales sticking out quite noticeably, with a very swollen opening that is all white (no sign of gravid spot where usually hers is quite noticeable). I've done a bit more research, could it be the acute version of dropsy?

In the picture above, she was using the driftwood to stop herself from floating upwards. She also lay under a leaf, before she became too buoyant even for that


Edit She's dead now. I did another water change and sterilised the breeding trap with boiling water. Going to LFS tomorrow (actually a very good one - specialist freshwater aquarium shop and aquarium gallery - nice guppy collection too!) to see what I can get to stop it happening again in the tank. Sheesh, this is worrying. I have pictures from after she was dead (out of the tank) - very bloated, way more than what's normal.

So sorry to hear of your loss, but shes either very bloated or was suffering from not been able to give birth.