Clownfish behavior?

[kartik_fish]

I have a question about one of my fish. It has been completely fine up until now, but today it has been staying mostly at the bottom of the tank, close to the intake in the aquarium. It occasionally swims upward, but returns to the same spot.

Earlier today it showed interest in food and chased it, but ended up spitting it out instead of eating. The other fish in the tank is behaving normally.

I’ve had both fish for about two weeks now, in a TMC Nano 60 liter aquarium. I cannot see any visible signs of disease — no mucus, white spots, or wounds. The fish is able to maintain its balance in the water, but it is breathing slightly heavier than the other one.

Any ideas what could be causing this behavior?

 

[Tahoe61]

Please provide an image of the clown with white lighting.
How old is the tank?
Providing specific values for specific gravity, ammonia, nitrates...

 

[kartik_fish]

Thanks for your reply.


I’ve now taken photos and a video under white tank lighting. It’s nighttime here in Oslo, so the room is dark, but I switched the tank light to white to get a clearer view of the fish.


Tank details:

• Tank age: about 6 weeks
• Fish have been in the tank for almost 2 weeks
• Salinity: 1.024
• Temperature: about 24.5°C
• Ammonia: 0
• Nitrite: 0
• Nitrate: very low (slight reading)

Let me know if you need anything else.

 

[kartik_fish]

Quick update:

Last night the fish became more active and behaved more normally, but it still did not eat. Both fish were swimming together high up in the corner of the tank, which is their usual behavior in the evenings.

Today it is back staying near the intake again. It showed some interest in food, but did not eat. I am feeding mysis (in brine), which it has eaten before without issues.

I have also attached a new video of the fish.

Any thoughts?

 

[sim]

Just started a tank with synthetic rocks, right? Enough oxygen? Are you sure about the tests? More details needed. Open the skimmer air to maximum and make the water surface move a lot.

 

[kartik_fish]

Yes, the tank was started with synthetic rocks.

I believe oxygen levels are sufficient — there is good surface movement in the tank. The skimmer is running, but not fully open, as increasing the air too much produces a lot of microbubbles. It is currently adjusted to a stable level.

Regarding water parameters (measured today):

• Salinity: 1.025 (refractometer)
• Temperature: 25.3°C
• Ammonia: 0
• Nitrite: 0
• Nitrate: 10

Test kits used: Salifert

The tank is about 6 weeks old, and the fish have been in for around 2 weeks.

 

[sim]

Yes, the tank was started with synthetic rocks.

I believe oxygen levels are sufficient — there is good surface movement in the tank. The skimmer is running, but not fully open, as increasing the air too much produces a lot of microbubbles. It is currently adjusted to a stable level.

Regarding water parameters (measured today):

• Salinity: 1.025 (refractometer)
• Temperature: 25.3°C
• Ammonia: 0
• Nitrite: 0
• Nitrate: 10

Test kits used: Salifert

The tank is about 6 weeks old, and the fish have been in for around 2 weeks.

Microbubbles are normal if the aquarium and tubing are all new. Turn the air on fully; the bubbles will disappear in 3 or 4 days. Put some activated carbon in a sock if you haven't already.

 

[Tahoe61]

Thank you for providing more specific details.
The fins appear clamped in my very unprofessional opinion.
This topic actually belongs in the fish disease forum. I will attempt to tag the forum experts.
@Jay Hemdal
@vetteguy53081

 

[vetteguy53081]

Yes, the tank was started with synthetic rocks.

I believe oxygen levels are sufficient — there is good surface movement in the tank. The skimmer is running, but not fully open, as increasing the air too much produces a lot of microbubbles. It is currently adjusted to a stable level.

Regarding water parameters (measured today):

• Salinity: 1.025 (refractometer)
• Temperature: 25.3°C
• Ammonia: 0
• Nitrite: 0
• Nitrate: 10

Test kits used: Salifert

The tank is about 6 weeks old, and the fish have been in for around 2 weeks.

This has nothing t do with rocks and I suspect you are getting false test readings and you can disregard nitrite which is freshwater specific and often associated with Api test kits which are less than reliable.
Is the fish breathing normal or labored?
Please post a video using bright white light intensity, no blue as images are a little fuzzy to see the fish's skin for issues.
I also intimidation from other clown may play a role here

 

[Jay Hemdal]

Quick update:

Last night the fish became more active and behaved more normally, but it still did not eat. Both fish were swimming together high up in the corner of the tank, which is their usual behavior in the evenings.

Today it is back staying near the intake again. It showed some interest in food, but did not eat. I am feeding mysis (in brine), which it has eaten before without issues.

I have also attached a new video of the fish.

Any thoughts?

Welcome to Reef2Reef.

Do know if these clowns are wild caught or tank raised?

Have you seen any white mucus feces from this fish?

The rapid breathing and stilted swimming pattern point to either Brooklynella or an internal coccidea disease. The latter isn’t treatable, brooklynelka requires medication that you may not be able to source - Ruby Reef Rally Pro. Formalin also works, but that isn’t really safe to use in homes.

 

[kartik_fish]

Thanks for the detailed response.

The clowns are wild caught, and I have not observed any white mucus feces.

This behavior has been ongoing since early yesterday.

Breathing is not completely normal, but not severely labored. Compared to the other clown, this one sometimes opens its mouth slightly when breathing.

It also shows some occasional twitching.

It often stays near the intake, occasionally swims up, then returns. The other clown behaves normally.

I have attached a new video under white lighting.

 

[Jay Hemdal]

Thanks for the detailed response.

The clowns are wild caught, and I have not observed any white mucus feces.

This behavior has been ongoing since early yesterday.

Breathing is not completely normal, but not severely labored. Compared to the other clown, this one sometimes opens its mouth slightly when breathing.

It also shows some occasional twitching.

It often stays near the intake, occasionally swims up, then returns. The other clown behaves normally.

I have attached a new video under white lighting.

The clamped fins does look like it could be the start of Brooklynella. This is VERY common in wild caught clownfish. You could try a 5 minute freshwater dip, but that will provide only temporary relief and is very stressful to the fish. Can you check with your local pet store to see if they carry any good medication for that?

 

[kartik_fish]

The clamped fins does look like it could be the start of Brooklynella. This is VERY common in wild caught clownfish. You could try a 5 minute freshwater dip, but that will provide only temporary relief and is very stressful to the fish. Can you check with your local pet store to see if they carry any good medication for that?

Thanks for the input.

It has now been over 36 hours since I first noticed the behavior, and the condition has neither clearly improved nor worsened. Wouldn’t you typically expect Brooklynella to progress more rapidly if that were the case, with the fish getting visibly worse over time?

That’s part of why I’m unsure if this is actually Brooklynella.

Another question:
I do see some biofilm buildup in the rear chamber of the tank. Could that potentially irritate the fish or affect the gills in any way?

 

[Jay Hemdal]

Thanks for the input.

It has now been over 36 hours since I first noticed the behavior, and the condition has neither clearly improved nor worsened. Wouldn’t you typically expect Brooklynella to progress more rapidly if that were the case, with the fish getting visibly worse over time?

That’s part of why I’m unsure if this is actually Brooklynella.

Another question:
I do see some biofilm buildup in the rear chamber of the tank. Could that potentially irritate the fish or affect the gills in any way?

Yes, that’s a bit slow for the typical progression of Brooklynella, but there is a lot of variation in that.

I don’t think the biofilm has anything to do with this. Besides, any water quality issue would affect both fish equally. Diseases like brooklynella may also affect both fish, but there can be a lag when one fish develops the disease before another.