My Vertical Molly

[sumocopter]

Hi, yesterday purchased two female mollies after my previous two died, I don't want my male to be lonely!

This morning one of the mollies seems to be unable to use her tail and is just floating around, occasionally sinking a little bit then floating back up. If she is anywhere but the surface of the tank she is vertical.

I've got a quick test kit which shows
pH:6.4
kH: 3d
NO3:25mg/l
NO2:0mg/l
gH:>10d
tank temp:27C
Sadly it doesnt show ammonia, but this test is the same as it always has been

Ive changed the water fairly frequently recently as I've been treating white spot which seems to have gone now, last change was 20litres just before I introduced the new mollies

Chemical Additives or Media in your tank:
Just chlorine control when I change water, all the filters in the Juwel tanks

Tank inhabitants:
7 neon tetras
3 mollies
5 zebra danios
5 five stripe barbs
1 sucking loach
1 red gourami

Recent additions to your tank (living or decoration):
2 mollies + gourami

Exposure to chemicals:
White spot treatment over the last 2 weeks or so

Firstly, any ideas why my two female mollies both died within a week, neither seemed particualrly out of sorts and it was a shock to find each of them dead in the morning, the male is fine.

Secondly, whats going on with my vertical molly?

Cheers for any help

 

[sumocopter]

I should add after i introduced the female mollies to the tank the gold molly (the one wit hthe vertical problem) got quite alot of hasle from the male, but no more than he gave to the other two while they were still alive. She didnt seem quite as keen to run away as the other two had been and the male did 'peck' her tail and along the side of her body at times, something that I've not seen him do before.

 

[WILDER]

How long did you climatise the new fish for.
Did the fish look bloated.
Sounds like swim bladder if the fish was struggling to maintain balance.
Does it look like the tail weighing her down in the water.