Sunken Belly

[okrazykat]

I don't know if I've ever noticed this before, or maybe it's getting worse...
Several of my discus have an area sunken on their body below the gills and above the base of the pelvic fins. It seems from a chart of discus anatomy that this is where the heart should be. Basically I would describe the area as the jowels or the neck.
The other two have nice fat flesh in the same area.
I know that they are just becoming sexually mature as they are starting to pair off and defend territories.
I don't think this area corresponds with stomach or intestines. I could post a photo if it would help.
I've had them for over a year in the same set-up. They all feed avidly, a mix of frozen bloodworm, krill, and shrimp, along with some Tetra ColorBits.
Tank stats are 110 gallon+, 82 degrees, NO3=0, pH=6.9, KH=3, NO2=0.
What do you think?

[okrazykat]

Here we go...

[okrazykat]

And...

[goldenpigeon]

mate they look ok to me. some of my fish have that. it is just how they are. some discus will have a "beak" under their gills between their belly which is the opposite of this (your fish are fine but the ones im talking about should not be bought). we all come in different shapes and sizes. as long as nothin looks majorly out of place i would say they are fine.

HTH

PS: i am not 100% sure about this. i might be wrong. mayb LR can tell you :D

[Merrilyn]

That looks like quite a pronounced dent in the body. Can you get a photo of a head on shot.

Not sure at this stage what it is. Have you ever used a worming preparation on these fish.

As far as your water parameters go, a zero reading of NO3 (nitrate) is a bit of a concern in a fully cycled tank. That being the end product of the process, there should be at least some reading. Can you check that test again please.

[okrazykat]

You're right about the low NO3. I just finished massive water changes to lower the phosphates which had climbed over 10+. The NO3 level was initially at about 12.5, now reading just over 0.
Never treated any Meds in the set-up.

[Merrilyn]

I'm starting to think that maybe that's just the shape of that little fish. There is certainly no hollowing above the eyes, like I would excpect to see in an emaciated fish. In fact, it looks quite well grown, and broad between the eyes.

I think you are doing everything right. That's just the way that fish is going to be.

[okrazykat]

I did have a runt that I got at the same time as these. They were all about an inch and a half. The runt never really grew. Ate like a horse. No sunken stomach or anything. Died a month ago. As small as it was, the others never picked on it.
Thanks for the help. I will continue to watch for any signs of worsening and post an update later on.