Zebra Fish Dying

[StevenF]

Each of the tanks testes were pretty consistent, here are the levels. 
Nitrate 5 ppm
Nitrite  0 ppm 
Total hardness 300 ppm 
Chlorine 0 ppm 
Total Alkalinity 180 ppm 
PH- 8.4  

Your water is too hard for the fish.  Zebra Danios are soft water fish.  They prefer neutral water PH (7)to slightly acidic (ph)6.5, a GH of less than 200ppm and your total Alkalinity might be too high.  Ammonia should be zrero but at 0.2 or less, I doubt it would kill you fish that fast.  You need softer water.
 
Below are links I used to determine the hard water limits for Zebra Danio.  
 
http/www.liveaquaria.com/product/prod_display.cfm?c=830+881+941&pcatid=941
http/www.fishtanksandponds.co.uk/calculators/hardnesscalc.html

 

[wake]

 

Each of the tanks testes were pretty consistent, here are the levels. 
Nitrate 5 ppm
Nitrite  0 ppm 
Total hardness 300 ppm 
Chlorine 0 ppm 
Total Alkalinity 180 ppm 
PH- 8.4  

Your water is too hard for the fish.  Zebra Danios are soft water fish.  They prefer neutral water PH (7)to slightly acidic (ph)6.5, a GH of less than 200ppm and your total Alkalinity might be too high.  Ammonia should be zrero but at 0.2 or less, I doubt it would kill you fish that fast.  You need softer water.
 
Below are links I used to determine the hard water limits for Zebra Danio.  
 
http/www.liveaquaria.com/product/prod_display.cfm?c=830+881+941&pcatid=941
http/www.fishtanksandponds.co.uk/calculators/hardnesscalc.html
 

Thanks for the input,  
 
Any recommended ways to soften the water?  

 

[the_lock_man]

So I bought the API mastering test kit.   From the tanks that killed my fish.  
Ammonia  .15-.2
Nitrite - 0
PH -  8.2
 
Do you think an Ammonia level like that would kill all fish in less then 12 hours?
 
 
Thanks 

 
No, I don't think ammonia at that level would do that to the fish that quickly. Had you already changed some water in that tank prior to taking the reading? If so, then the ammonia reading at the time would have been significantly higher, so that would probably explain it. However, if not, then there's another cause - or combination of causes including slightly raised ammonia.
 

 

Each of the tanks testes were pretty consistent, here are the levels. 
Nitrate 5 ppm
Nitrite  0 ppm 
Total hardness 300 ppm 
Chlorine 0 ppm 
Total Alkalinity 180 ppm 
PH- 8.4  

Your water is too hard for the fish.  Zebra Danios are soft water fish.  They prefer neutral water PH (7)to slightly acidic (ph)6.5, a GH of less than 200ppm and your total Alkalinity might be too high.  Ammonia should be zrero but at 0.2 or less, I doubt it would kill you fish that fast.  You need softer water.
 
Below are links I used to determine the hard water limits for Zebra Danio.  
 
http/www.liveaquaria.com/product/prod_display.cfm?c=830+881+941&pcatid=941
http/www.fishtanksandponds.co.uk/calculators/hardnesscalc.html
 

 
I personally don't think that water hardness is a significant issue. Ideally, yes, you would keep all fish at their ideal pH and KH levels, but softwater fish can do well in hard water. They are usually very resilient to raised ammonia, they used to be known as a starter fish, back in the bad old days when fish-in cycling was all we knew how to do. That's how I cycled my first tank - zebra danios in a high pH. They all survived, and I was by no means an expert at that time, I did pretty much everything wrong (I'm not really an expert now!)

 

[Ch4rlie]

Hmm, seems we're not getting the answers of why this is happening to your danios.
 
Have to agree that the ammonia and water hardness levels would not help but would not kill your stocking this quickly.
 
A couple more questions to try and see what may be happening -
 
Do you have any live plants in these tanks?
 
How did you clean this tank prior to adding substrate, decor and equipment?
Did you use bleach, detergents or soaps etc?
 
Do you use anything to clean the tank glass such as spray cleaner?
 
Was the tanks you got new or second hand?
 
Are there any aerosol products, such as deodorants or hair sprays being used in the same room or nearby?
 
Like Byron mentioned earlier, thinking there may be a good chance there is something toxic in the tank water thats affecting your stocking.

 

[Bubbelzzz]

As there are no tubes or anything not aquarium safe used, softeners couldn't be the issue. There is for me a concern by releasing the fish so quickly. They might get a shock of the abrupt change in pH and hardness and die of this shock. On the other hand, this didn't happen at the 20 gallon tanks so it isn't very likely. I find it very strange that the fish in your 20 gallon tank are fine while the ones in the 10 gallon die instantly.
What are the exact differences between these tanks except the size of them?
 
I agree with Byron as well (thats why I asked about the softners), that there is something toxic in these tanks.

 

[Byron]

I am in agreement with others that the ammonia according to the test numbers would not normally be expected to result in fish deaths so quickly, but keep in mind that with the high pH ammonia is more lethal that the same level would be at say pH 7, and at pH 6 ammonia at this level would not be toxic at all since it would be ammonium.  So the high pH must be kept in mind as a significant factor.
 
I also agree that the high GH would not kill fish so suddenly.  I have looked into water parameters for fish species a fair bit over the past several years.  The problem with soft water fish in hard water is that the internal physiology is affected over time to the point where the fish just dies before its normal lifespan is reached.  This length of time depends upon the fish species and the GH.  The main issue is usually the accumulation of hard minerals, particularly calcium, in the kidneys (the kidneys remove the calcium from the tank water when it passes into the fish) which become blocked and the fish then dies.  Studies on cardinal tetra showed that the higher the GH, the shorter the lifespan.  However, the hard water does immediately cause the fish's physiology to work much harder, as it is now dealing with regulating the blood pH and other things, so the fish is weakened from the start.
 
Acclimation can be fatal, but if these fish were purchased locally one would assume the water parameters of the store water are similar if not the same as the water used in the tanks, but I am only surmising.  The so-called pH shock is more often a TDS/GH shock, according to many of the sources, but both are connected.
 
The questions asked by Ch4rlie are very important.  One has to rule out (or confirm) possible issues one by one.
 
Edit.  You asked about softening the water...this is possible, but a bit involved.  We can go into this once we establish the issue (if we can).
 
Byron.

 

[StevenF]

osted Today

, 06:15 AM

StevenF, on 23 Nov 2015 - 9:52 PM, said:

 
Quote

Each of the tanks testes were pretty consistent, here are the levels. 
Nitrate 5 ppm
Nitrite  0 ppm 
Total hardness 300 ppm 
Chlorine 0 ppm 
Total Alkalinity 180 ppm 
PH- 8.4  

Your water is too hard for the fish.  Zebra Danios are soft water fish.  They prefer neutral water PH (7)to slightly acidic (ph)6.5, a GH of less than 200ppm and your total Alkalinity might be too high.  Ammonia should be zrero but at 0.2 or less, I doubt it would kill you fish that fast.  You need softer water.
 
Below are links I used to determine the hard water limits for Zebra Danio.  
 
http/www.liveaquar... 941&pcatid=941
http/www.fishtanks...rdnesscalc.html
 

Thanks for the input,  
 
Any recommended ways to soften the water?  

 


 

Get a revers osmosis system.  It filters out most of the minerals.  My RO system generates water with GH of about 25ppm.  I have to add micro nutrients to the water otherwise my plants die.  My sisters tap water is at about  300ppm. In fact it is officially not safe to drink according to the EPA.  It  tastes like metal.  Typical scale removers do work on scale this water leaves behind.
 
 Most people think KH is mainly a measurement of how much calcium and magnesium is in the water.  It isn't.  In fact with RO water saturated with calcium and magnesium carbonate you cannot get a KH above 80 and a PH of about 7 (in my experience).  However if you add sodium bicarbonate you can easily get above 120ppm.   
 

We can go into this once we establish the issue (if we can)
 

.One test you could do is to go the store and buy a 5 gallons of distilled water or get some water from someone with a RO system.  That along with you tap water should get your GH down to about 150ppm.   If fish survive at this level you probably have your answer.  However this involves putting the lives of more fish in danger.
 
I think you need a detailed lab report listing all the minerals in your water.  Without a detailed lab report or a test with live fish we probably would not be able to come up with a definitive answer.  What city do you live in? Have you looked for your cities water report on line?  If it is not city water but instead well water, the well should be checked out.

 

[wake]

Okay, sorry this has taken so long to update.  
 
The two fish in the 20 gallon tank are doing well.  The ammonia levels are at .15 ish, 0 nitrite, and about 40 ppm on the nitrate.  The ten gallon tanks are at .1 ish on the ammonia, 0 nitrite, and 20 ppm on the nitrate.  I put one zebra in each of the 10 gallon tanks a week ago and they are alive.  
 
I now am wondering if I can add more.  I am thinking about adding one more to each of the ten gallon tanks and adding 3 more to the twenty gallon tank.  What do you think?
 
To answer charlie's questions.  The 20 gallon is an old tank, the 3 10 gallon tanks are brand new.  We did not use anything to clean the tanks and just rinsed them out.  No live plants or gravel are being used.