Two Mollies Dead In 48 Hrs?

[entersandman]

I have lost one golden and one black molly in the last 48 hrs and i have no idea why!!!
My water parameters are all fine i have checked and double checked these, PH 8, Ammonia 0, Nitrite 0, Nitrate 40.
All the fish seemed totally fine swimming about, feeding etc yet Sat afternoon i go to feed them and a black one is floating on the top of the tank.
Sunday morning a yellow one is dead at the bottom of the tank.
The yellow one did have a big tummy until about a few days ago and then it disapeared so i guess it might have been pregnant???
All my other fish seem fine, Gouramis, Plecs, Rainbow Fish, Danios and Tetras.

I'm a bit baffled by this!!!! Any ideas as to what it might have been or anything i can do to make sure my other mollies will be ok, Apart from the yellow mollie lying at the bottom of the tank for 24hrs before it died i couldn't see any other symptoms of illness so i'm not sure what to do!!!

The worrying thing is another of my yellow mollies has also started lying at the bottom the tank so i'm worried this little fella is going to go the same way!!??

Help!!!

 

[Suicidal_AZN]

what kind of gouramis, rainbow fish, danio and tetras???
certin types of those fish can be aggressive.

 

[LauraFrog]

Mollies need salt. Lying on the bottom of the tank - complete inactivity - sounds sorta like a very bad dose of the shimmies. Hard to know from not having seen the fish and I'm no expert, but go to the Livebearers forum and read the pinned topic Mollies Need Salt.

 

[entersandman]

what kind of gouramis, rainbow fish, danio and tetras???
certin types of those fish can be aggressive.

There has been no aggression it's a very peaceful tank, Honey Gouramis, Neon Tetras, Rose Tetras, Blue rainbows, Pearl and Zebra Danios.

 

[WILDER]

Mollies do better in brackish water but with the fish he keeps he cant turn it to brackish.Need to look at your water stats in ammonia,nitrite,nitrate,and ph.Laying on the bottom can be bacterial to parasite.The fish bloated up could it maintain its balance in the water.What does it look like when the fish go to the toilet.What do you feed the fish.Have any fish darkened in colour.Signs of shimmies is a fish swimming in place and getting no where.

 

[entersandman]

The fish were not bloated up though one of the yellow ones was for a few weeks before but i think it was pregnant rather than bloated, it just sat at the bottom of the tank not really moving much. I feed them Tetra Pro flake food and frozen food twice a week. They don't seem darker in colour except when i think the yellow one was pregnant then it's belly was a darker colour. The black Molly had been swimming around fine, never on the bottom and just seemed to die for no reason i could see at all!!! All the fish maintained their balance fine as well.
All water stats are fine by the way as i mentioned in my first post.
Do you think a anti-bacterial med would be worth putting in the tank to be on the safe side??? If so what one would you guys recommend.
Like i said i have another yellow molly looking like it's going the same way

 

[WILDER]

I would add anti internal bacteria med by interpet.
Check out what it looks like when the fish go to the toilet.
Good luck.

 

[entersandman]

Thanks for your help Wilder much appreciated, i'll get some on the way home tonight, the yellow molly seemed ok last night but i don't want to take any risks as i've become quite attached to my fish!!!

 

[WILDER]

Good luck.