Silver Mollies, Cute, But Normal?

[tameem]

I got like 4 fairly good size silver mollies. They are so cute, and when Im working in the tank, or have my hands in it, they dont seem to get too afraid and often come up to me. I like that they tend to hang out at the top, but often they seem to be sucking at the surface. No other fish does that, just they do frequently.
Is this normal behavior?

Also, do they readily take flake food? Some type I notice they dont accept.

Thanks for responses!

 

[Superfly]

I know Gouramis and Bettas suck at the surface because of their Labyrinth organ. It allows them to inhale atmospheric gasses and use them to breathe. Never heard of Mollies with a Labyrinth organ though. Strange...

 

[Corleone]

They aren't labyrinthine. In any other fish, sucking at the surface is a sign that they're not getting enough oxygen. It could be depleted, nitrite could be preventing their blood from absorbing enough, or they could be suffering from something wrong with their gills.

 

[tameem]

That sounds pretty serious if thats the case!
What do I need to do??? I didnt think it was an issue with O2 because no other fish have that problem. It's only them, and not all of them.
I have tetras and swordtail and none of them do that.
I also have a powerhead to help with circulation
So what shoudl I do?

 

[Hawkins]

increase their oxygen supply (unless you think it is enough)

and do water tests for nitrite and nitrate. if nitrite is above 1, do a water change or if nitrate is above 20 i would do one

 

[tameem]

I added a 4" round airstone today to help with circulation and oxygenation.
Nitrates were at 20ppm, and my nitrites are 0.

Also, I noticed sometimes a silver molly will behave strange, swimming almost vertically for a few seconds. Whats up with that?

 

[darklady]

i found that my mollies did that a while ago when i had a problem with my pump and the oxygen level wasn't where it should be.

i found that once i had cleaned my filter using old tank water and did a water change all was ok but i kept a close eye on them just to be on the safe side.

i also found i had a molly acting oddly like that this morning but it soon sorted itself out once i tried to put it into a net so whatever was wrong with it was resolved by me chasing it with the net. my partner found it funny, i did not.

i feed my fish all flake food which they all take and mollies in my tank will take flakes from my hand. they also have brine shrimp and bloodwroms as well as daphnia and catfish pellets. my whole tank get a varied diet. i am sure some will disagree with me but i speak as i find myself.