Sick Pygmy Cory?

[CrazyDiamond88]

Hi guys, I was just looking about my tank seeing as my pygmys didn't seem to be coming out for food as much lately.
 
I spotted one little guy sitting there and when I put the net near, he just sat there.
Usually these guys speed off, quick as a shot.
But he moved a little then settled back down. So I scooped him up with the net (which normally I can't do as they are so fast), and I've put him in a little jug of water with some food.
 
He's very inactive... he seems to be gilling rapidly... apart from that I'm not sure what's different.
 
I will do a water test in a bit, too.

 

[CrazyDiamond88]

I thought it may be because the tank had built up quite a lot of algae, and there wasn't much oxygen.
 
So I cleaned lots of the algae out and changed about 70% of the water.
 
Will see what is happening with him tomorrow. I put him back in the tank.

 

[CrazyDiamond88]

Does anyone think my oxygen idea could be it?

 

[Klonoa50]

Hi there!
 
I'm very new at taking care of fish myself, so hopefully someone else will come along and be able to help, but figured I'd try my best to answer and ask the preliminary questions that usually crop up.  
 
From what I've read on cories before, if they're having breathing trouble their gills will turn red/transparent (I'm guessing the same holds true for Pygmies, but I'm not sure).  So if his gills are red that might be it.  If the other 7 are doing ok it seems unlikely it'd just be oxygen, or I would've thought all of 'em would be having that problem.
 
Has the tank been set up for a while?  Do you know the ammonia/nitrite/nitrate readings?  

 

[CrazyDiamond88]

Hey!

His gills seem pretty normal... Though it's hard to tell since he's so small. But they're definitely not red.

The other 9 are fine so that's why I'm puzzled.

Yeah the tank has been up for at least 6 months. I haven't had a chance to do a reading lately. I'm not home right now and I will do one as soon as I am.

 

[Klonoa50]

Welp that about kills my limited knowledge...

 I did some looking around on the web but didn't find much.  It's really weird that only one of 'em appears to be having an issue.  I'll try n' do some more reading up and see if I can't find anything... 
 
Is the betta acting strange at all?
 
Also forgot to mention earlier, that tank in your siggie is very pretty.  Is that the one with the cories n' betta?

 

[CrazyDiamond88]

The betta is fine actually. Hm.
 
Yeah, that's the tank, though it looks different now. I'm going to re-scape soon and make it low-light and easier to care for.
 
My water test results:
 
ph - 7.6
Ammonia - 0
Nitrite - 0
Nitrate - 5

 

[CrazyDiamond88]

okay, just found a dead pygmy in the tank

 

[Klonoa50]

Sorry for your loss.  
 
I did more research and couldn't find anything useful... at least whatever it was doesn't appear to have affected the other cories.