Balloon Molly Pop-Eye

[alexge]

I have had a Balloon molly for about 2 months now.
 
She is solo in an Amazonian freshwater tank (low ph at 6.4, low hardness) which AFAIK is not the environment that mollies thrive in.
She was however bred and kept at ph 6.8-7.0 (LFS told me so).
 
My water quality is top-notch, I do 50% pwc every week, monitor PH, Ammonia, Nitrite and Nitrates.
 
Two days ago I noticed that the balloon molly had developed pop-eye, only one of her eyes was swollen and had a cloudy-whitish look.
Immediately I quarantined her in a 20 litre tank, and I started treating with Pimafix and Myxazin and Epsom salts.
 
Today, the cloudy film appears to be gone, and the eye is less swollen, but still considerably larger than the other.
 
What could have caused this?
My LFS insisted that she should be ok in my tank, and she didn't seem stressed or otherwise annoyed the past two months.
Is this some kind of bacterial infection, or just an accident?
 
 
 

 

[the_lock_man]

I haven't kept mollies for years, but when I did, I found them to be very susceptible to single-eye popeye, pretty much every one I ever had suffered from it at one point or another. I'd suggest do a water change every other day until it goes away.
 
As you point out, mollies don't thrive in low pH, low hardness water. It may have been bred in similar water, but that doesn't change its basic physiological need. They need to absorb some of the minerals that are found in hard water, because that's how they have evolved. In much the same way, if humans don't absorb (eat) enough iron, we become anaemic, if we don't get enough vitamin c we get scurvy, if we don't get enough calcium, we get rickets.
 
Mollies also need slightly brackish water.

 

[alexge]

I was cautious about buying a molly, but the bloke at the LFS insisted she'd be fine...
Sadly both tanks I have are acidic water (not soft though).
Interestingly enough I noticed today that two of my tetras have a white fuzzy fungal infection.
My water params are fine, so I'm guessing its some kind of pathogen in the tank attacking the most vulnerable fish (both tetras had been bullied before).

Would epsom salts help with the brackish factor, or do I need aquarium salts?

 

[eaglesaquarium]

I'm going to disagree with my learned colleague... mollies do not require salt, but they do require harder water, as he points out.  The salt part is not accurate.  Other than that, everything he said is dead on.

 

[the_lock_man]

If I could point my learned colleague in this direction here
 
http/www.fishforums.net/index.php?/topic/137887-mollies-need-salt/
 
This article was written for us some time ago, by Dr Neale Monks, a highly respected aquarist.

 

[eaglesaquarium]

If I could point my learned colleague in this direction here
 
http/www.fishforums.net/index.php?/topic/137887-mollies-need-salt/
 
This article was written for us some time ago, by Dr Neale Monks, a highly respected aquarist.

 
That is correct, he did write that, but I believe that information has been superseded.
 
I don't have time to post a counter to that article, but will in the future.