Too Large A Water Change Causing Fish To Die?

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ap4lmtree

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Two of my kuhli loaches died today, one was found dead in the morning and one i found dead in the evening. I think the evening one was happy glass surfing in the morning too. and the first one was glass surfing the night before.

I am not sure, but i think the morning one might have died because he got cut or had a bruise. Maybe the plastic plate i put in the aquarium to put in the water fast hit him or something causing him to bruise. Or maybe he got somehow.

However, for my second kuhli loach, i am left that maybe it was because i did too large of a water change. For two days before he died, i did a 85% water change, and maybe i should do just 50% water changes.

the first one died in the morning and the second picture is the evening one:

Y9SCru0.jpg


tedkHrT.jpg
 

RSababady

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Thats rough. Sorry to hear about that.

Two things:
1. Have your water tested to see what is in it in terms of Nitrates, Nitrites, Ammonia, pH
2. Check if you are using the right amount of water safety (Tetra water safe or seachem prime) for your volume of water change.

Let us know what the answers to the two questions are and we can take the guessing out of the responses
 

JesseMoreira06

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If your fish are used to it , it is completely safe to do huge water changes without any problems occurrng. It only becomes a problem when ur nitrates are very high ex:100ppm for a few weeks and then you perform a large water change, in that case it' better to do 25% for a few consecutive days.
 

AvalancheDave

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Large water changes magnify the various dangers of water changes:
None of those things are a problem if you're only doing a 10% water change.

Large water changes are a different story altogether. If your fish survive it's because they're tough and/or you were lucky. Your luck may run out one day.

If your fish are used to it , it is completely safe to do huge water changes without any problems occurrng. It only becomes a problem when ur nitrates are very high ex:100ppm for a few weeks and then you perform a large water change, in that case it' better to do 25% for a few consecutive days.
That nitrate thing is a myth.
 

Junne

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Large water changes can be a problem if your parameters are different from the water you are taking out/versus putting back in such as ph is different from the tank to whats in the tank, temps are too different, etc

I do ( and have always done for the past 7 + years ) a 50% water change every 2 weeks with no ill effects. Yes, if the parameters are different, they can suffer from shock and I believe that you should not do more than 50% every water change. It's not necessary to do more than that each time.

It's very possible that the loach deaths were coincidental and maybe they were ill to begin with. How long have you had them and if they are new, how did you acclimate?
85% water change may not have been the cause. I have done at least that much before too. What are your readings? Ammonia/Nitrite/Nitrate/PH - have you tested ph from your tap vesus whats already in the tank?

I'm sorry for your loss.
 

JesseMoreira06

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Large water changes magnify the various dangers of water changes:
None of those things are a problem if you're only doing a 10% water change.

Large water changes are a different story altogether. If your fish survive it's because they're tough and/or you were lucky. Your luck may run out one day.



That nitrate thing is a myth.
What your saving is a myth , I've been fish keeping for over 10 years with 15 tanks currently , I always do 50-60% water changes weekly and occasionally
70-80% on surten tanks , I've never had any fish deaths due to this , in fact my fish seem to thrive and enjoy it.
 

AvalancheDave

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I usually drain the water until dorsal fins are showing. That's 95% or so with no issues. In the beginning, I noticed my fish breathing rapidly after water changes but didn't investigate the issue. I also noticed lots of bubbles forming on all surfaces but didn't investigate the issue. Winter came and I did a larger than usual water change (40%?) and fish went from stressed to dying. That's how I learned about gas bubble trauma. I began heating water outside of the tank which solved that problem.

A few years later, I had more fish die and I learned that RO filters don't always remove chlorine.

Both issues were things I could get away with if I did small water changes but became problems with larger water changes.

With the correct technique, large water changes can be safe.
 

AvalancheDave

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What your saving is a myth , I've been fish keeping for over 10 years with 15 tanks currently , I always do 50-60% water changes weekly and occasionally 70-80% on surten tanks , I've never had any fish deaths due to this , in fact my fish seem to thrive and enjoy it.
I assure you, chlorine toxicity, gas bubble trauma, temperature shock, and salinity shock are all scientifically proven (your anecdotal evidence notwithstanding). Nitrate shock is without any scientific evidence.
 

Junne

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I assure you, chlorine toxicity, gas bubble trauma, temperature shock, and salinity shock are all scientifically proven (your anecdotal evidence notwithstanding). Nitrate shock is without any scientific evidence.
Chlorine toxicity is only if you do not properly treat the water which I assume anyone in the fish keeping hobby will automatically do that. As for gas bubble, if you are stirring the substrate when cleaning ( and or have bottom dwellers that do that ) and you don't have very deep beds of substrate, it should never be an issue. This is rare for this to happen in a home aquarium.
 

JesseMoreira06

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I assure you, chlorine toxicity, gas bubble trauma, temperature shock, and salinity shock are all scientifically proven (your anecdotal evidence notwithstanding). Nitrate shock is without any scientific evidence.
No I don' have any scientific reasonings what I have is experience within the hobby and I can assure you as long as your temp matches you can do 80% water changes daily if you choose to.

I do and many other hobbiest do large water changes weekly.

As long as you know how to properly do a water change the amount doesn' matter.

EDIT: @Junne has a very valid point. I'm not a science kinda guy haha.
 
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AvalancheDave

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Chlorine toxicity is only if you do not properly treat the water which I assume anyone in the fish keeping hobby will automatically do that. As for gas bubble, if you are stirring the substrate when cleaning ( and or have bottom dwellers that do that ) and you don't have very deep beds of substrate, it should never be an issue. This is rare for this to happen in a home aquarium.
Have you ever tested for chlorine after dechlorinating water? I test each time and found that I had to add many times the recommended dosage of dechlorinator before chlorine was undetectable. In addition, you can't trust the water treatment company to keep chlorine levels consistent.

Chlorine isn't a problem if you do a 10% water change. If you do a 90% water change then a little left over chlorine can be an issue.


Gas bubble trauma has nothing to do with the substrate. In the context of a water change, it results from gas supersaturation due to heating cold water. Gas emboli form in the fish which can be fatal.

Again, this is benign with small water changes and potentially lethal with larger water changes.
 

AvalancheDave

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No I don' have any scientific reasonings what I have is experience within the hobby and I can assure you as long as your temp matches you can do 80% water changes daily if you choose to.

I do and many other hobbiest do large water changes weekly.

As long as you know how to properly do a water change the amount doesn' matter.

EDIT: @Junne has a very valid point. I'm not a science kinda guy haha.
It's great that you've been lucky so far. There has been a surge in postings on various aquarium forums where people have done large water changes or transferred fish between tanks and have had the fish become stressed out or die.

Telling people that large water changes are completely safe because you haven't had any problems is a disservice to the hobby. Not only is it merely anecdotal evidence but it misinforms people and can result in further fish loss.
 

JesseMoreira06

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It's great that you've been lucky so far. There has been a surge in postings on various aquarium forums where people have done large water changes or transferred fish between tanks and have had the fish become stressed out or die.

Telling people that large water changes are completely safe because you haven't had any problems is a disservice to the hobby. Not only is it merely anecdotal evidence but it misinforms people and can result in further fish loss.
I will keep telling others that large water changes are completely safe because they are regardless as to what your saying, you can' tell me I've been lucky for 10+ years in the hobby without a single fish dying from this issue , With 15 tanks , not exactly sure how many fish I have in total but over 200 for sure , I guess their all extremely hardy.

No matter what links you send to me , I still stand by large water changes are completey safe , As long as you know what your doing it's fine. People have been doing them for years and years and continue to this day and will continue.
 

AvalancheDave

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I will keep telling others that large water changes are completely safe because they are regardless as to what your saying, you can' tell me I've been lucky for 10+ years in the hobby without a single fish dying from this issue , With 15 tanks , not exactly sure how many fish I have in total but over 200 for sure , I guess their all extremely hardy.

No matter what links you send to me , I still stand by large water changes are completey safe , As long as you know what your doing it's fine. People have been doing them for years and years and continue to this day and will continue.
Falling back on anecdotal evidence and digging their heels in is usually what people do when they lose a scientific (or otherwise) debate.

Here's an idea: I've never had ich. Maybe I should go around telling people it's not a problem.
 

JesseMoreira06

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The article you sent kinda said exactly what I stated , if your fish aren't used to large water changes because you haven't done one in a long time and Nitrate is high then a large 80% water change can put fish into shock , if your doing weekly 60-70% or even 80% water change nothing will happen to them.
 

JesseMoreira06

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Falling back on anecdotal evidence and digging their heels in is usually what people do when they lose a scientific (or otherwise) debate.

Here's an idea: I've never had ich. Maybe I should go around telling people it's not a problem.
haha to funny, tap yourself on the shoulder. Do you feel satisfied? I can only imagine your experience within the hobby..a Betta in a 2.5 gal?

I stated right from the get go , I don' have any scientific evidence only experience.

"John" fish only died cause he hadn't
ever done a water change PERIOD , so of course doing a super large water can effect the fish. I'm talking about if you do regular weekly or even twice a week or daily large water changes nothing will happen to your fish.

Ich is a whole different scenario.

can you send me a link that actuslly proves your point? Where large weekly water changes can actually harm your fish.

Pm me if you'd prefer and sorry to the OP for getting off track.
 
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Cricket lynn mclean

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It seems clear there is a misunderstanding here. As far as I have read we don't know much about the op's tank. Is it new and the water changes are from an ammonia spike? Or 2 years old and she normally does 1 a month. Personally I do VERY large water changes all the time. In fact in some tanks I change maybe 75 as much as daily (fry). Typically I change about 66% twice a week to weekly.

I think Jesse is assuming that the water changes are done properly. That is pretreating the water and matching temp. I'm sure there are cases where large changes are bad. Perhaps in a tank with tons of tannins causing a large ph change. I think the key is to keep your maintenance regular and to know your issues. Like Dave knows his water is heavily chlorinated. I have really hard and high water and even though I use leaf litter and wood for my fish I can still do Water changes the way I do Water changes. Which is at least once a week I change at least half but more typically I change more and more typically I change more often. In my fry tanks I will change a lot and often but they are bare with nothing affecting tank water parameters.

I thought originally the issue was gonna be bio but no one is saying that. But just to be clear the bio in the water isn't enough to make a difference even if you changed 90% assuming you have a properly seeded filter.

I typically would assume that large water changes are good for fish. Especially angelfish.
And any death is likely attributed to something else. If large water changes are unusual for you and you are doing one then I'm going to assume there is a reason why. Like illness. Or cycling. Or something funky going on. That's just generally speaking. Of course there are always exceptions. I'm guessing Jesse is assuming he's speaking to someone who knows to match temp and dechlorinate. And Dave is assuming nothing just in case they don't know this.

Just keep swimming
 
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toolman

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If you are doing regular water changes weekly (40%+), a larger % ( I also sometimes change up to 80% routinely) water change is harmless IMHO. However if the water parameters are hard to match or you don't routinely change water a large change can be deadly.

@ap4lmtree...As long you were doing water changes before and properly matched water parameters, I believe the water change probably wasnt the cause.
Many breeders I know would agree with @JesseMoreira06 and commonly change large %'s, but if you dont a large change can be harmful. Hope we have answered your questions.
 
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