RTC Help

[thebiggerthebetter]

Yes, washing filter media coinciding with the problem would be a big red flag to check but the OP states ammonia zero, nitrite zero, tank mates are good. Is it the norm or the current readings you are citing?

At the face value of all the info given, I'd continue to think the RTC problem is RTC-specific and not a water problem.

 

[pittbulldogva]

The filter rinse was a few weeks ago. The parameters cited are current.

My wife and I checked him for barbs tonight. Nothing. I also looked in his mouth and didn't see anything of any interest. I did note his belly looked particularly bloated for not having eaten in a while. Not firm, but larger than expected. I took a short video of him and this is typical of his behavior. He'll lay in front of the filter output and then swim in a circle and come back. I checked the water again tonight. Amm - 0 Nitrite- 0 Nitrate - 10 or less. I'm going to try to load the video in the next post. In the video you can see the Alligator Gar. A few months back, his right gill swelled up, and he started coming to the top regularly and opening his mouth, presumably using his labarynth organ to breath. The swelling went down, but now there is part of the gill that looks white and "ragged" that can be seen in the video. I've treated with salt, and Crystal Clear Wipeout.

 

[fishdance]

Something is definitely not quite right. Fish is showing stress behaviour.

I would boost the dissolved oxygen level with a strong shower head or spray bar onto suspended fly screen or tumbled over rocky media etc.

Some salt would help to thicken its gill slime coat.

Are you confident the nitrite is zero? Fish behaviour suggests nitrite, are the gill filaments brown? They should be a healthy blood red.

 

[pittbulldogva]

I can buy a new test bottle today and check, but my kit is not that old.

Something is definitely not quite right. Fish is showing stress behaviour.

I would boost the dissolved oxygen level with a strong shower head or spray bar onto suspended fly screen or tumbled over rocky media etc.

Some salt would help to thicken its gill slime coat.

I added salt at 1 Tbsp per 10 gallons about a week ago. I'm interested in the spray bar on the screen. I've never heard of that before.

 

[wednesday13]

Id still wager it possibly got “tagged” by one of the rays or ingested a barb. IME when a fish has been stung they swell up and gasp like that. It could last for weeks until the venom runs its course. Ive had some fish pull through and others drop ??‍… luck of the draw. It def. looks bloated. If its made it this far it might pull through. Fish ive lost from bad stings were bloated/swollen and dead within 24 hrs.

 

[Fishman Dave]

The nitrate test is being done correctly ?

it might sound a basic question but I come across many people who forget that the nitrate test requires bottle 2 to be shaken for a long period and then once added the vile needs shaking again for a period, and then you need to leave it 5 minutes to colour up before taking the reading.
Sorry if you are doing it right but worth asking.

I do worry that the bottom jaw looks a little like a dislocation rather than a simple gaping mouth.

 

[pittbulldogva]

I was concerned about the dislocation as well. I'm not sure what I could do about it if it is though. I follow the instructions to the letter on the nitrate test to the letter.

 

[thebiggerthebetter]

FWIW I continue to think alike with Wed13 - stung by a ray. Mind you I've never had rays.

In all my years I have never seen this symptom - mouth stuck open - except on one of our koi that has had it for about a year now for no good reason. I've not come across it secondhand either ever. Not that I am all knowing but this tells me it is a pretty rare condition in my world - I don't keep rays and almost never read about them in the peer posts, except when such ray on non-ray interactions are reported or asked questions about.

It seems to never be a good idea to combine other bottom dwellers with rays, especially large, assertive catfish. Sooner or later rays will lit them up.

 

[fishdance]

How is the RTC doing today? Did increasing the dissolved oxygen levels help with symptomatic stresses?
Using a trickle screen is to boost the efficiency of dissolved oxygen rate. Similar to adding a small air bubble trickle into the impeller of pumps to create a cloudy mist of micro bubbles. Much more effective than a venturi on the output side (although you could do both). If you have pure oxygen cylinders, rig up a reaction chamber.

If your nitrite kit hasn't expired, the reading should be fine. Usually fish colors are dark and vivid with nitrite issues.
I would not be worried about nitrate, I often have levels at 200 - 250 ppm without issue.

Getting tagged by a ray seems to be the most likely cause but you should see a missing barb on rays or an injury site on the catfish. Eating a discarded barb shouldn't cause any issues. I haven't seen a dislocated jaw on a RTC. Their head shape and jaw muscle strength is very robust.

 

[pittbulldogva]

No change. He is still hanging out in front of the output and occasionally making a lap. I didn't see any damage on the RTC, but he's been acting strangely for a while now. We did find a discarded barb from the small ray a few weeks ago in the bottom of the pond. I think the ray got him. Hopefully he'll start coming around sooner than later.