Poorly Fish

[James Bond the fish]

Not sure if this counts as an emergency, but...

Recently got two female swordfish to put in with my male, one HUGE pregnant one and one normal-sized. Both were very active with wide spread fins. My male chases the huge one all over the place relentlessly, while mostly leaves the normal one alone.
The problem is, the normal one's started being very sick. She spends almost all her time hiding inside my dark log where I can't really see her unless I take the lid off. She doesn't come out at feeding times, and the very rare times I have seen her she has her fins clamped to her body and she's not really swimming, just staying in place. Every other fish in the tank seems 100% fine, even the other two swordfish and my guppies. I've done a water change, but she isn't perking up at all. Is this something I can "cure", or is she already doomed with no hope...?

 

[WILDER]

Need to look at size of tank in gallons or lites.
How many fish and which type.
Water stats in ammonia,nitrite,nitrate,and ph.
If one fish is huge he will be waiting to take a snack off the fry.
Livebeares need one male to every three females to reduce the stress.
The female thats hidng does it look skinny.

 

[James Bond the fish]

The tank is 3' x 1' x 1', not sure how many litres. Contains corys, black widows, guppies and some small shrimps. Ammonia 0, Nitrite 0, PH 7. And the poorly fish is the one the swordfish has been ignoring, so I doubt it's stress from him. The fat one looks fine and doesn't seem to be too bothered by his affections.

 

[WILDER]

Hiding away can be parasites to bacterial.
Water stats look fine, but you don't have a nitrate reading.
Does the fish look skinny, or pale.
Check the gills to see if they look pale with excess mucas or red and inflamed.
What does it look like when the fish goes to the toilet.
Check the anus to see if its enlarged or red and inflamed.
Any signs of flicking and rubbing against objects, or darting about.

 

[WILDER]

Livebearers are very prone to internal parasites as when you buy them from the lfs most of them can come from the wild.

http/www.flubenol.co.uk/