# Shrimp and softened water



## Brad99 (Sep 27, 2006)

Hi All,

I woke up to find all my shrimp dead this morning (dozen). I know what happened but not why? I have very hard well water, have been adding potassium (EI Dosing) for months. Tank has been stable for quite awhile now.

Since I'm now using potassium chloride as the salt for the softener, I did my first 50% water change with potassium softened water (which I read elsewhere is ok for planted tanks). (have been doing 50% changes for months while on well water)

Temperature remained constant during the change, pH was 6.9 before change, 7,0 after change, and 6.9 in the morning (my target)

Ok, obviously the softened water is the only new variable here.

My question to all you knowledgable people is what do you think the deaths were caused by? Too quick of a change in hardness? Less calcium - replaced by potassium in the water? Something else I forgot about??

In hindsight, I should have probably did a 20 % change from the hard to soft water a few times over the week rather than the 50% at the end.

There doesn't "appear" to be any stress on the fish (actually look quite happy). We'll see if the plants are affected later I guess. 

I suspect I may have shocked the shrimp inadvertently. Now that the initial shock has happened, do you think it's ok to restock the tank with new shrimp? Or have I created a hostile environment for them. 

I'm sticking to the softened water for convienience (180 gal tank - tired of hauling hard water from the basement) so if it means no more shrimp so be it. But if it means "properly" acclimatizing some new inhabitants, I'll go get them.....

Thanks


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## John N. (Dec 11, 2005)

Sorry to hear about your shrimp catastrophe. Were they cherry shrimp?

I think you have it right, the sudden change in parameters caused the shrimp deaths. Too quick of a change in hardness that they couldn't adjust to. I think if you acclimate the next batch of shrimp to your new soften water, the shrimp will be okay. 

-John N.


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## milalic (Aug 26, 2005)

Brad99 said:


> Temperature remained constant during the change, pH was 6.9 before change, 7,0 after change, and 6.9 in the morning (my target)


I doubt a change in ph of 0.1 will kill your shrimp. Did you use dechlorinator and which one? Does it removes heavy metals? Did the temp between your water in the tank and the water you were changing were the same?



Brad99 said:


> My question to all you knowledgable people is what do you think the deaths were caused by? Too quick of a change in hardness? Less calcium - replaced by potassium in the water? Something else I forgot about??


It is really hard to know what went wrong. It is probably something related to one of the parameters. Change in hardness will not kill your shrimp like that. I keep shrimp in almost RO water and vary the hardness. Shrimp take calcium from their food and not only from the water.



Brad99 said:


> do you think it's ok to restock the tank with new shrimp? Or have I created a hostile environment for them.


Restocked it.

-Pedro


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## Catch and Release (Dec 30, 2006)

For what it's worth, I had something similar happen to me under similar conditions. I use a KCl-based water softener and after a 50% water change, I found a couple dead cherry shrimp. The next week after another 50% water change, more shrimp bodies. The following week, after another 50% change, another fatality of what I believe to be the last of them. 

The last one I actually saw die and it was really weird. The shrimp flew across the tank a couple inches below the surface and basically did a nose-dive to the gravel where it just twitched a little bit and died.

I wonder if the excessive amount of potassium kills them? I think it's odd that in my case they died off slowly a couple at a time every week. I would have assumed if it was the potassium they would have all died at the same time right off the bat, but who knows?


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## Kenshin (Feb 26, 2007)

The cause of your shrimps death is the amount of potassium you put into your tank to make it soft. Your potassium level is probably too high to create a osmotic shock for the shrimps in which the shrimps are losing their body water content to their environment (your tank) and hence a lot of them start to die. 

In order to soften your water the right way, you should use a diluted acid such as muriatic acid (sold in your hardware stores for cement) or HCl (if you can gain access to them). Just add several drops to your tank (depending on size and how hard your water is), and wait for 1 day to circulate completely, then measure pH. Or you can just use RO water instead.


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## ihooklow (Sep 20, 2006)

Acid cannot actually soften water, can it?

I am trying to do the HCl + CaCO2 = ? But it seems that the minerals would, unless this caused the minerals to precipitate out of solution, still be in solution, and therefore still contribute to KH/GH, right?

Maybe my Inorganic Chemistry is too rusty.

I understand that acid can overcome the alkalinity of the aquarium and therefore, eventually, lower the pH.

But soften?


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## oblongshrimp (Aug 8, 2006)

no acid will not soften your water it will just lower the pH.


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## littleguy (Jan 6, 2005)

oblongshrimp said:


> no acid will not soften your water it will just lower the pH.


agreed.


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## YuccaPatrol (Mar 26, 2006)

Muriatic acid = Hydrochloric acid (HCl)


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## toddnbecka (Sep 20, 2006)

Won't the acid soften the water by reacting (dissolving) carbonates? Remember, there are 2 different elements of water hardness, GH and KH. The KH determines the stability of the pH, and the pH won't drop, or will drop briefly then rebound, until the KH is neutralized. Adjusting water chemistry can be a real hassle, r/o is the easiest way to work with it.


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## littleguy (Jan 6, 2005)

Muriatic acid (HCL) will not reduce GH or KH.

GH is defined by the amount of Ca and Mg ions in solution. Adding HCL or any other strong acid will not change the number of Ca or Mg ions in solution. In fact, if there are calcareous rocks in the tank, a strong acid will shift the solubility equilibrium point of Ca and Mg and actually increase the GH of the tank.

KH is defined by the amount of equivalent HCO3 ions in solution. I say equivalent, because there is a dynamic equilibrium between CO2 (dissolved carbon dioxide), HCO3 (bicarbonate ions), and CO3 (carbonate ions) in solution. That is, bicarbonate is constantly "rebalancing" itself with CO2 and CO3:

CO2 <--> HCO3 <--> CO3

The relative quantity of CO2, HCO3, and CO3 is determined by the pH of the water - they are in a dynamic equilibrium. If you reduce the pH using a stong acid, the equilibrium point will shift towards dissolved CO2. If you increase pH using a strong base, the equilibrium will shift towards CO3. But ultimately, changing the pH does not affect the amount of carbonates in the system - _it only affects the form of the carbonate (co2, hco3, co3)._ The carbonates never vanish from the system, they just shift appearance. At least this is how I have always understood it.


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## mrbelvedere138 (Jan 18, 2006)

toddnbecka said:


> Won't the acid soften the water by reacting (dissolving) carbonates? Remember, there are 2 different elements of water hardness, GH and KH. The KH determines the stability of the pH, and the pH won't drop, or will drop briefly then rebound, until the KH is neutralized. Adjusting water chemistry can be a real hassle, r/o is the easiest way to work with it.


Agreed. Don't fight the water. Use an R/O if you need soft water. I think every household should consider one. It has so many uses to justify the cost. Houseplants, humidifiers, jewelry, aquariums, clothesirons, etc.


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