Clown Loach Emergency - 16 yr tank sudden problems

Loachstrong

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I have a well established clown loach tank that has had no changes in a very long time. These fish have been living together with no additions or new stock for 16 years. They have been in this particular well water for over a decade and in this particular tank with these particular filters for 6 years.

Suddenly, this week, seemingly out of the blue I noticed some tell tale signs of distress. One Loach began clamping fins and swimming vertically near the top of the water. Tests confirmed elevated nitrates, but nothing out of line for this tank. And 2 water changes in back to back days brought those levels down. Ammonia zero. Nitrite zero. PH the same as it has always been for the last decade or so (well water that is very stable).

That initial loach is doing worse every day. And now a second loach has started to show similar symptoms. A third has begun flashing.

This all has a very bad feel to it. I've lost entire tanks before, long ago, and it started a lot like this.

I'm mostly confused because nothing has changed in this tank. I very specifically kept this thing static for years and years and years to avoid introducing problems. And yet, here I am. Other than continuing water changes to keep the nitrates down, do you have any advice or ideas?

Is it possible a pathogen of some sort was introduced in some other way? Food? The well water? Something else? Or is it possible I'm seeing a bad reaction to high'ish nitrates that they used to tolerate?

I'm pretty desperate at this point. Thanks for reading.
 
How many clowns, and what's the total tank stocking? Pics and/or video of the tank and fish please?

Since you mention high nitrates and the age of the se up, had it been a while since you'd last done a water change? How much of the water do you typically change how often?

If you can copy/paste and fill out the template below please, the better the chances that people will be able to help! Since we can't see the tank or fish for ourselves, we really rely on getting as much detail from you about the whole set up and routine as possible to try to figure out what's happening.

Tank size:
tank age:
pH:
ammonia:
nitrite:
nitrate:
kH:
gH:
tank temp:
Filtration:

Fish Symptoms (include full description including lesion, color, location, fish behavior):

Volume and Frequency of water changes:

Chemical Additives or Media in your tank:

Tank inhabitants:

Recent additions to your tank (living or decoration):

Exposure to chemicals:

Digital photo (include if possible):
 
Tank size: 125 gal
tank age: 6 years (current stock together for 16 years without additions)
pH: NA
ammonia: 0
nitrite: 0
nitrate: currently 20ppm, but was possibly as high as 80ppm recently
kH: NA
gH: NA
tank temp: 80f
Filtration: fx6 + fx4

Fish Symptoms (include full description including lesion, color, location, fish behavior): Fin clamping, rapid breathing, swimming vertically near surface, not eating

Volume and Frequency of water changes: On average 20% a week. Sometimes longer in between. My memory is weak, but it might have been on the longer side this last time, which is not unusual for this tank.

Chemical Additives or Media in your tank: none

Tank inhabitants: 4 clown loaches and 2 small plecos that have all lived together for 16 years

Recent additions to your tank (living or decoration): New heaters about 2 months ago, new valves and O Rings on the filters about the same time, otherwise no changes (at all) over the course of the life of this tank

Exposure to chemicals: None that I'm aware of

Digital photo (include if possible):
 
Just to be sure, when you say "no changes" does this mean no decor (from other tanks) or live plants have been introduced for months?

Next, do you share equipment in the loach tank with others tanks? This means nets, gravel vacs etc? If so is there any sign of issues in any of other tanks or have yo added fish etc. to any of these tanks?

As you should have figured out by now I am trying to rule out things to help eliminate the obvious. What is obvious is this must be something contagious if a disease or parasite/worm. Of course it could be some other for of contaminant.

The behavior suggests a few things but does not make them certain. Hanging near the surface suggest things that affect the ability of the fish to get oxygen. But your testing says it isnt ammonia or nitrite. So this suggests something else that effects the gills. Do either of the fish effected so far show any signs of rapid breathing or flared gills. Is the vertical one hanging near a filter output a lot?

Re being vertical, does the fish try to get horizontal and fail? This would then suggest something that can effect the swim bladder which could be any number of causes. Is the fish eating and pooping? If so can you see the condition of the poop? I have never seen mine poop in 19+ years. But i know they must do so.

Finally, this could be a neurological problem. Some form of infection or parasite/fungus. This might have been present for some time and needed to reproduce before it began changing the fish behavior. I can offer nothing if this is the case.

None of the above will help that much I am afraid. However, flashing usually means an external parsite and these can be affecting the gills. Both Ich and velvet can do this. Ich is easy to spot but velvet (Oodinium) can be hard to see. However, the same things are used to treat both. I have a few clowns for a bit longer than yours. I know how freaked out I would be if this were in my tank.

I see this as being a difficult choice, I think this potentially could wipe out the tank since it appears to be spreading. This means action needs to be taken and this is difficult to do if there is no certainty for what to treat. If you take your best guess and go with that and are wrong, it may make things even worse. Even if you dose the wrong med. which does no harm, the time spent treating with it would mean the problem only gets worse in that time.

Without knowing more I would hesitate to suggest anything here, But if you feel compelled to act and bre wrong than to do nothing, I would go with Velvet (Oodinium) as the thing for which to treat. However, This is a choice you need to make as I do not want to be responsible for making the wrong choice here. I should probably have kept my mouth shut. But as a clown lover, I could not do so. One more thing. Velvet can be hard to see. One way to help with this is to turn out the lights and shine a flashlight on the fish. This can make the velvelt more easy to spot.

The best solution here would be the scientific approach which means a microscope and gill and skin scrapings and poop examination, this could identify or rule out parasites.

You might want to move the initial patient to an H tank to treat there with your best guess. That way if it is the wrong choice and is also harmful in this situation, you will do no harm to anything else. Also, a bare bottom H tank will let you see any fish poops. If you have some fake plants you can add to the tank or a clean rock behind which it can hide, that will make the fish feel a bit less stressed. Make sure the tank is well aerated. You do not need a cycled filter if you can do a 50% water change daily or every other day at worst. Bear in mind if you are medicating th tank that you must replace the amount of med removed with the water change unless another dose is due that day, In this case do the full dose after you do the water change.

If the fish is still eating, this would let you feed medicated food if needed. You can find medicated food treated with Metrodinazole or an antibiotic online. Also, you can make your own.

Any more info you can add re some of the above should help in narrowing down what is wrong. I wish I could have offered some more helpful ideas. But diagnosing a lot of things is difficult when we can see them in person. Doing it remotely makes it even harder to get right. Some decent pics might help but they also may not if the cause does not offer visible symtoms.

Other people may have a better idea than anything I have suggested. Further, I am far from certain your problem is Velvet. So please take what I think for what it is, a best guess and as likely to be off the mark as on.
 
I'm a little concerned that with only 20% water changes weekly, and possibly missed water changes at times too (as you said has happened) and with the very high nitrates, that this might be a case of "old tank syndrome", where nitrates have been steadily building for a long time, other aspects of the water chemistry have also been drifting and becoming quite different from the source water over the course of time - it's a common problem with tanks that have been running for so long without other issues, and the fish having had plenty of time to gradually get used to the changing parameters, yet this having a chronic long term affect on their health and rising stress levels, until it reaches a breaking point and their problem with it becomes more obvious.

@Essjay @Colin_T @TwoTankAmin @Byron @Wills @Slaphppy7 , any thoughts?

I want to include a word of caution, because usually when there's a health concern, large water changes done rapidly is our suggestion and potential remedy, and good first aid even if there is another cause or disease that will need further treatment. However, if there is some old tank syndrome happening, then the differences in the tank water and the source water will be too large, and changing them so rapidly without giving the fish time to acclimate can lead to shock and then death.

So as a first step, while people try to help figure this out, I'd suggest reading up on how to fix old tank syndrome. I dealt with it when trying to fix the problem in a tank I inherited from my dad, where the nitrates were so high, they were off the chart for the API freshwater kit to test. It took several water changes over the course of days, just to get them to a readable level, and even longer spent doing small water changes one or two days apart, gradually increasing the amount and frequency, until things were back in a safe range, and the tank water as a whole was chemically close enough to my tap water that I'd be able to change 50% or more at once.

So slow and steady is the key, giving the fish time to adjust.

I wonder if the temp is also a little high for clowns? Especially if they're gasping and finding breathing harder, so perhaps knocking down the temp a few degrees could help in the meantime?
 
Just to be sure, when you say "no changes" does this mean no decor (from other tanks) or live plants have been introduced for months?

Next, do you share equipment in the loach tank with others tanks? This means nets, gravel vacs etc? If so is there any sign of issues in any of other tanks or have yo added fish etc. to any of these tanks?

No new fish, no new decor, no plants. And been that way for 6 or so years. I only have the one tank so no threat of cross contamination. The only thing that has changed in recent months is new heaters, some new valves and O-rings on the filters, and somewhat recently (since maybe December) some new food - veggie pellets from the LFS. Is it possible the food was contaminated with a parasite or pathogen?

My best guess at this point, and I have no way of knowing if this is even possible, is that the nitrates spiked without me catching it quick enough and it stressed the fish and made them weak and susceptible to.... something? But given the true isolation of this tank, it's basically been in its own quarantine for so many years, how would any pathogen even make it's way in there. Unless something has always existed, hanging out for 6 years, and just now took hold due to nitrate stress?
 
somewhat recently (since maybe December) some new food - veggie pellets from the LFS. Is it possible the food was contaminated with a parasite or pathogen?

Are they eating any other foods, or just the veggie pellets? Since they're mainly carnivorous? Are the veggie pellets a commercial, packaged product? (name?)
 
I'm a little concerned that with only 20% water changes weekly, and possibly missed water changes at times too (as you said has happened) and with the very high nitrates, that this might be a case of "old tank syndrome", where nitrates have been steadily building for a long time, other aspects of the water chemistry have also been drifting and becoming quite different from the source water over the course of time - it's a common problem with tanks that have been running for so long without other issues, and the fish having had plenty of time to gradually get used to the changing parameters, yet this having a chronic long term affect on their health and rising stress levels, until it reaches a breaking point and their problem with it becomes more obvious.

Yikes. This was my wife's first thought too. And, unfortunately, I panicked and did some big water changes before it dawned on me as a possibility. 40 to 50% in back to back days to try to bring those nitrates down. I've backed off, but fear if this is the case I might have caused more damage.

In this scenario, would these symptoms be from general stress and malaise due to water quality issues (and then a large swing back)? Or is it possible that a pathogen is somehow in play and just recently presented itself due to that stress? I'm not sure how the latter works, especially in my situation where this tank has been isolated for so long and (theoretically) not exposed to pathogens.
 
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Are they eating any other foods, or just the veggie pellets? Since they're mainly carnivorous? Are the veggie pellets a commercial, packaged product? (name?)
Yeah, they primarily eat shrimp, bloodworms, raw veggies, etc. The veggie pellets I recently added to the diet are a packaged product, but comes from a local chain store in my state... not a national commercial product, in other words. It's really hard for me to imagine how they could be a factor here, but it's the only tangible thing that's changed recently.
 
Yikes. This was my wife's first thought too. And, unfortunately, I panicked and did some big water changes before it dawned on me as a possibility. 50 to 40% in back to back days to try to bring those nitrates down. I've backed off, but fear if this is the case I might have caused more damage.

In this scenario, would these symptoms be from general stress and malaise due to water quality issues (and then a large swing back)? Or is it possible that a pathogen is somehow in play and just recently presented itself due to that stress? I'm not sure how the latter works, especially in my situation where this tank has been isolated for so long and (theoretically) not exposed to pathogens.

Since the fish have survived the water changes you did, then I doubt you made anything worse! I might even be completely wrong about old tank syndrome playing a part - I just wanted to include that caution since nitrates were so high and you've said it's not usual for it to go for longer stretches between water changes. And I also completely understand the panic reaction and rushing to do large water changes when you spot a problem!
I'm no expert on water chemistry, nor on diseases I'm afraid. So please don't take my advice as gospel or expert either, as @TwoTankAmin said about his, and he is far, far more knowledgeable and experienced than I am.

Just from my own experiences with an old, long established tank with old tank syndrome though, and the research I did around it then, yes, I do think it can continue for a long time, gradually building up and stressing the fish, until either something happens (like a dead fish and ammonia spike) that tips it over the edge, or it just finally reaches a point where the fish are so irritated and stressed by the degrading conditions that they go over the edge. Think of it as being in a room that is slowly, ever so slowly filling with a toxic gas, or smoke. It's barely noticeable at first, but it begins to irritate, sting your eyes, make you feel itchy, but only bugs you a bit. But you have to live and sleep in it and breath it in for days on end. And the amount keeps increasing gradually, until it's also getting harder to breathe now, and your lungs are burning...
You get the idea. If you were in that situation, the irritation and stress alone would be a constant, and not being able to escape it as it gets worse could easily make you frantic. Any other additional problem would only be harder for you/your health to handle, because you're already dealing with the effects of this chronic source of irritation and stress. That's how I visualise fish must feel in a tank with slowly rising ammonia/nitrates/nitrates, given the effects of these toxins in chronic or acute levels on fish physiology.

There were a pair of yoyo loaches in the tank I inherited, and sadly lost them to an ammonia spike when my dad had turned the filter off on the tank without telling me. They showed similar frantic behaviour before passing away. I think since loaches are scaleless, they're even more prone to their skin being irritated by adverse effects in the water, so the flicking may be a result of that.

I think a pathogen is unlikely, given what you've described with no new stock/plants etc for so long, but it doesn't hurt to do a test for something like velvet using the flashlight test @TwoTankAmin mentioned. But again, not a disease expert, and there are lots of naturally occurring bacteria etc in our tanks that can be both beneficial and harmful under different circumstances. I hope Colin or others I tagged above can provide further advice there!
 
OK- now I am getting a better idea of what might have happened. Most fish have some level of defense against many pathogens. However, this can be weakened by stressful conditions as noted.

Next, a lot of pathogens and or [parasites can be present in a tank but at levels low enough for the fish's defenses to protect them, until something change the balance- like stress.

Old tank syndrome causes pH to drop a lot. This makes any ammonia present way less to completely non-toxic. Suddenly raise the pH and this turns it toxic very fast. The fish may adapt somewhat to the OTS parameters but then a big water change alters these radically. That can really stress fish.

Finally, I would not rule out the new veggie food. This could have caused the fish to become plugged up. The only way to know this is if the fish looks to be getting fatter and to be able to see it is not pooping. Constipation can cause internal pressure which can then press against the swim bladder. But an internal bacterial infection can do the same thing. However, if the food is the cause, it should affect some of all of the fish which ate it. But it may also be that one or two fish really pigged out vs the other fish getting smaller portions. So it could be an overeating issue.

As you can see diagnosing fish diseases is difficult at best and without the ability to take scrapings and view things under a microscope. If the fish are eating I would stop feeding the and would then see if you can feed the symptomatic fish crushed fresh peas. Frozen can work, but look for salt free or low salt. Defrost before feeding with frozen.

I am reluctant to suggest any meds without know with some certainty what is wrong. A lot of diagnosing has to be done by eliminating things. Then what is left become the most likely culprit. the problem is such a trial and error approach may have a fish die before one can determine the cause.

Again I wish I could suggest something more solid. But the information available so far does not point to something specifc with any degree of certainty. Since the only thing that has changed is that food, this stands out as a likely potential cause. But that doesn't mean it is.
 
How are the clowns behaving now, @Loachstrong ? Any improvement, decline, or about the same? Are they eating at all? Wondering how they're responding after the recent water changes.
 
The water might have been too cool? At least with the shimmys raise water to the low 80's and add antifungal medication. Water changes help too.
 

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