Is My Fish Possibly Sick?

[Seed]

Got sold a Tropheus duboisi recently. It's a tanganyikan cichlid in a mbuna tank, but it seems to have fit in well, isn't harrassed nor does it give harassment overly much. It exhibits normal cichlid behavior in most respects, i.e. stakes out its spot, chases other but doesn't nip or give lengthy chase, etc. Got it because my wife liked it a lot and convinced me to get it.

The fish looks healthy. Its body is plump (but not bloated), and it's coloration appears normal, it isn't faded or milky. Its fins are not nipped. There is no sign of ich or fungal infections. There are no sores or anything abnormal about its body at all. I have carefully looked at its gills and they seem normal, not bruised or bleeding. It isn't respirating heavily either, respiration looks like I'd expect it to, but I'm no expert.

What it's doing is swimming near a particular rock, turning on its side, and then very quickly rubbing against the rock. It does this with both sides of its body. It is a very quick maneuver. It does not do this obsessively, but from time to time. I have seen the behavior ever since it has been in the tank.

Is this normal behavior for this fish, or is it something I should be concerned about?

Water parameters:
NH3 = 0

NO2- = 0

NO3- = 20

PH = 8.0

GH around 214 ppm
KH around 179 ppm or so.

 

[WILDER]

The fish shouldnt be turning on its side that can be swim bladder to parasites.
Check the anus to see if its elarged or red and inflamed.
What colour is the poo when it goes to the toilet.
Is it just rubbing itself on the rock.

Just want to make sure the fish is not turning it self to onside just to rub as that could be normal.
Usually when they turn to oneside when swimming thats not normal.

 

[Seed]

The fish shouldnt be turning on its side that can be swim bladder to parasites.
Check the anus to see if its elarged or red and inflamed.
What colour is the poo when it goes to the toilet.
Is it just rubbing itself on the rock.

Sorry, I should have worded that different. I was trying to describe the maneuver itself, it doesn't swim on it's side at an y other time except for when it is doing this rubbing thing. It just does a quick turn when it wants to do this particular maneuver. The whole maneuver takes less than a second to complete. Anal area appears normal. Poo is brownish, not dissimilar from its food.

I should point at that for whatever reason, the fish only does this on horizontal surfaces, it does not do it to any of the verticle or semi-verticle rock in the tank. In fact, there is only one rock in the entire tank that it does this to.

 

[WILDER]

Ok I would just keep an eye on him for now.
If it gets any worse get back to the board.
Make sure the fish dosn't produce more slime coat.

 

[Seed]

Thanks very much. I'll keep an eye on it. Honestly I probably would have ignored it except I saw some posts here recently about flashing and I wasn't sure if this behavior was what that referred to.

 

[WILDER]

Fish to rub now and then, but if there doing it quite often something usually wrong.
What temp is the tank set at.

 

[Seed]

Tank's at 76 degrees F, or about 24.5 degrees Celcius.

 

[WILDER]

Thats fine.
I would maybe ask in the cichlid part of the forum just to be on the safe side.

 

[Seed]

This has gotten worse in a day. The fish is now hiding constantly. It keeps its fins close to its body all the time. It rubs on the rocks a lot more than I first observed, and it does this odd behavior where it shakes its head around as though trying to shake something off. I still can see nothing at all on its body, no increased slime coat, no specks of whiteness, eyes are clear, looks scales look healthy, fins aren't rotted or spotty. Its body is black with white spots (typical juvenile coloring for this species), in the black areas I can't see anything ich-like.

If it is a parasite, will malachite green treat it? I'm asking this because while it is acting sick, it is still extremely difficult to catch. I will have to remove most of the rock in the tank to do this, which is no small undertaking, and increases my chances of damaging the tank itself due to the size of some of the rocks. Treating it in the tank, if it will not disrupt my filter, is the most desireable option for me.