PLEASE HELP (Oscar fish weird behavior)

[revanblaze]

Have you tested your water?

Yes

If yes, what is your ammonia?

0ppm

If yes, what is your nitrite?

0ppm

If yes, what is your nitrate?

0ppm

If I did not test my water...

...I recognize that I will likely be asked to do a test, and that water tests are critical for solving freshwater health problems.

Do you do water changes?

Yes

What percentage of water do you change?

21-30%

How frequently do you change your water?

Every two weeks

If I do not change my water...

...I recognize that I will likely be recommended to do a water change, and water changes are critical for preventing future freshwater health problems.

Hello everyone, please only respond if you have experience on the matter, thank you for your time

tank set up
size: 180 gallons
fish: 1 Adult Oscar fish, 7 silver dollars, 1 Adult pleco, 1 Adult bichir
water parameters: PH 7.1, Ammonia 0ppm, NO2 0ppm, NO3 0ppm
filtration system: UV filtration, Fluval fx6, 2 airstones, airstone filter
temp: 76 F
live plants and fake plants, as well as rock hides and driftwood

had silver dollars living on the other side of a divider for a while they grew a bit bigger for 4 months. removed it and have been living peacefully for about a 3 weeks. the Oscar is 4 years old and has lived its whole life with the bichir. was recently moved into the 180 gal from a 75 gal 8 months ago. It's lived about 8 months with the pleco and occasionally harasses it, but rarely even sees it

What is the problem:
I love this oscar fish more than anything, I had him transported across the US when I moved after getting things set up (had my parents take care of him while I set everything up). he's been here for now 9 months. hes appeared healthy since a month ago. recently I tried introducing another oscar who was a bit smaller than him and very non aggressive from a 75 to the 180. had them separated by a divider. decided it would be better for them to be separated and put the smaller one back into his 75. during the time they were in the tank together I think their may have been signs of hith forming on my adult oscars head (one fairly big hole on his side, but only a faintly light spot on his forehead). I treated the whole aquarium with general cure. (Water parameters had a slight ammonia spike previous to this about 2 weeks after cleaning my filter to about .25ppm) re-stabilized the aquarium with a 50% water change after treatment. its been about a week now and hes(idk how to post videos here I will try) been spending most of his time on the right side of the tank and he'll bot in circles, or left and right rapidly and aggressively. I am very worried about this behavior as he's never really done it before. today he's just been hanging out on the right side of the tank doing this behavior. I'm also severely worried about the potential hith and am planning to do a second wave of treatment tomorrow. I think the first wave did help as the one hole seems to be healing. I've been extremely nervous and worried for my oscar, I just want him to be happy and healthy life. I'd appreciate some advice, Idk what this behavior is, the tank is well aerated, his gills and fins look healthy, he doesn't eat very much, but is eating his food. Thank you for reading

 

[revanblaze]

 

[Deadeye]

Good looking Oscar and tank!
Oscars are weird fish…
I wouldn’t expect this to be related to HITH - that doesn’t cause any behavioral issues that know of. But I’d double check your nitrates, 0 is hard to believe in any tank that also has fish in it. Especially when only 30% is changed every 2 weeks and the inhabitant is an Oscar.
If this started after introduction (and removal) of another Oscar, it’s possible you are looking at territorial (or breeding) behavior.

 

[tlindsey]

I wonder if something is going on with the Oscar’s nervous system.
Is that behavior non stop?

 

[revanblaze]

I wonder if something is going on with the Oscar’s nervous system.
Is that behavior non stop?

very frequent, he seems to calm down every once in a while taking breaks and then getting back to it, I believe he does stop for a longer period at night. he also has control when swimming, hes not crashing into things at least

 

[revanblaze]

Good looking Oscar and tank!
Oscars are weird fish…
I wouldn’t expect this to be related to HITH - that doesn’t cause any behavioral issues that know of. But I’d double check your nitrates, 0 is hard to believe in any tank that also has fish in it. Especially when only 30% is changed every 2 weeks and the inhabitant is an Oscar.
If this started after introduction (and removal) of another Oscar, it’s possible you are looking at territorial (or breeding) behavior.

I really hope its territorial behavior, but its just so frequent rn, I'm so worried

 

[LBDave]

The HITH doesn't look that bad (advanced) in the pics. But look for any pinholes at the infection site. I had a female oscar (4.5 years) that got HITH and it affected her brain. Had to put her down.
I didn't treat her because previously she had healed from HITH with care and almond leaves.
If I had a do over I would have treated with metro (in the water) for 2 weeks. Right away. Just straight metro not General Cure.
My male oscar got a trace of HITH. Not too bad. The metro cured it.
And I do 70-80% water changes weekly on both my tanks. 110 gal and 230 gallon.
76 degrees may be a bit low but I don't think it's the source of the problem.

 

[duanes]

To me a 20 to 30% water change every 2 weeks is inadequate, and not enough to ward off chronic HITH.
In fact, I would find a 20-30% water change once per week inadequate to ward off HITH, especially with all those other fish in a 180 gal.
In my 180, with heavily planted sump. I try to do at least a 30% water change every other day, with much less stocking than what you appear to have.
Below my heavily planted sump sump
.
I know to many that regime might seem excessive.
But since you love that oscar.....you need to get to the root of the problem, and I expect, it's too few, and too small water changes, unless you brought in a new fish without QTing it
If it were me, and I saw the onset of HITH, I'd ramp up my water changes to at least a 50% change per week, and see if that makes a difference over the next month or so.
Since HITH is chronic and takes time to infect, I wouldn' expect to see any change for the better until at least a month has past, and if there is no improvement, I'd work up to say, two 40% water changes per week.

 

[scottts210]

The HITH doesn't look that bad (advanced) in the pics. But look for any pinholes at the infection site. I had a female oscar (4.5 years) that got HITH and it affected her brain. Had to put her down.
I didn't treat her because previously she had healed from HITH with care and almond leaves.
If I had a do over I would have treated with metro (in the water) for 2 weeks. Right away. Just straight metro not General Cure.
My male oscar got a trace of HITH. Not too bad. The metro cured it.
And I do 70-80% water changes weekly on both my tanks. 110 gal and 230 gallon.
76 degrees may be a bit low but I don't think it's the source of the problem.

General Cure is metronidazole with praziquantal. Shouldn't that work also? What dosage Metronidazole do you recommend?

 

[duanes]

Meds are a good jump start, but are really only a temporary bandaid.
The bacteria that cause HITH are ubiquitous (always there, always waiting to infect) if water conditions aren't pristine.
In nature riverine fish such as oscars, are living in nearly constant 100% water changes.

Note the flow of the river in the shots above, and below I took in S America not long ago, where Oscars are commonly found


If you don't constantly get a foothold on what causes HITH, it will continue to reinfect
And that initial onset, is usually due to a lack of enough water changes.,..

Whether this infection is more an internal infect, manifesting itself by burying into the brain, instead of external (sores on the head) is impossible to ascertain without internal analysis.