Heavy metals effect on shrimps

[Sami]

I have recently lost 5 red cherry shrimps and I must say it's been also financially quite a loss, because they cost 8 euros per shrimp.
Losing 40 euros once in a while is not what a student can afford.

Couple a years ago our local water company started to add combined chlorine instead of gaseous chlorine to the tapwater.
The aquarium society I belong to guided us to use either sodiumtiosulfate or ascorbic acid (vitamin c) in order to neutralize chloramine, by splitting the bond between chlorine and amine-group. As I study chemisty I guessed that using compounds that contain sulphur, may be noxious to fish and other aquatic critters - so I decided to use ascorbic acid.

But after I lost those 5 red cherries I thought about other factors that could have caused the death of shrimps. Heavy metals was one of them.
How much of the following substances can shrimps take (in brackets you can see the values that my water company gives in mg/L):

Al (0,02)
Fe (0,03)
Cu (0,004)
Mn (0,002)

Other water values that are measured from my shrimp-aquarium:
pH 6,8
GH 3-4 dH
KH 2 dH
NO3 <10mg/l
NO2 0
Temp. 24-25 C

No added fertilisation and no CO2 addition


Once I saw one of the shrimps die. It was walking normally untill it fell over to its side. It tried to get up, but didn't manage. Next mornign I saw lots of "empty jackets" in the tank because the other shrimps seemed to have molted.

What could have caused shrimps death?

(The text may seem to be a little unfocused. The simple reason is that I'm in fever while writing this - don't hesitate to ask if you didn't get it )

[Polypterus]

Hi !
Copper ist very dangerous for shrimps - when have CuSO4 inside they gonna die ;( perhaps have to use an filter agains heavy metals.
Sometimes they get under some conditions also problem to change the sin and can die. When have a copper pipe in the house you should let the water first run some time and not use warm water, better cold water - less Cu would get in. Ot use water from your garden - perhaps better for them.
Florian

[Polypterus]

Hi !
You ahve other shrimps doing well with your water - so pperhaps problem cause of skin changing in fresh water after putting them in your tank after buying... I had been buying some time ago some caridina simoni simoni, and they died fast, - the water from the dealer seemed to be old and they wanted to change skin but get problems.
Last year I bought caridina simoni simoni at an meeting, and they do fine now ...
Florian

[Sami]

Hi !
Copper ist very dangerous for shrimps - when have CuSO4 inside they gonna die ;( perhaps have to use an filter agains heavy metals.
Sometimes they get under some conditions also problem to change the sin and can die. When have a copper pipe in the house you should let the water first run some time and not use warm water, better cold water - less Cu would get in. Ot use water from your garden - perhaps better for them.
Florian

Hallo Florian,

I can hardly believe that such a little amount of copper (0.002 mg/l) can do harm to the shrimps.
Even though I have copper pipes in my house, all my other shrimps are doing just fine - green shrimps are even breeding with amazing speed. What kind of amount of coppersulfate (or which ever salt of copper that harms shrimps) has been noticed to cause problems?

I never change the water in the morning, when the tapwater hasn't been run for hours. Even when I do change the water I usually let the water run for some while before running it into aquarium.

What kind of filtering do you suggest to collect heavy metals - I've never heard about such thing used in aquariums. Ion replacement?

Collecting water in garden isn't such a good idea in a big city like Helsinki - I bett I'd get far more harmful subtances in the water than in my tapwater

Hi !
You ahve other shrimps doing well with your water - so pperhaps problem cause of skin changing in fresh water after putting them in your tank after buying... I had been buying some time ago some caridina simoni simoni, and they died fast, - the water from the dealer seemed to be old and they wanted to change skin but get problems.
Last year I bought caridina simoni simoni at an meeting, and they do fine now ...
Florian

Are there some specific factors that make molting impossible for shrimps? Lack of certain minerals or wrong water parameters?
All the other shrimps seem to have no difficulties in molting.

I do know that if the shrimps can't change their skin, they will die to lack of oxygen. So the reason that caused my shrimps to die may have been that they weren't able to molt. What could have caused this?

[Polypterus]

Hello !

Well, i just listen to Mr. Quante few weeks ago and he tell, that when have copper pipes should be very careful. He have an description about his tanks and water treatment withCARBONIT Monoblock Multifunktion Filter here : http://www.wirbellose.de/anlage/index.html cause of copper pipe in his flat.
But when you already have success with the other shrimps, so I think that there had been problem in the water before. Perhaps some Medicament at the petshop ...
florian

[Sami]

Are there some specific factors that make molting impossible for shrimps? Lack of certain minerals or wrong water parameters?
All the other shrimps seem to have no difficulties in molting.

I do know that if the shrimps can't change their skin, they will die to lack of oxygen. So the reason that caused my shrimps to die may have been that they weren't able to molt. What could have caused this?

Can anyone answer these questions?

I've heard that iodine has *something* to with skin changing, but I cannot remember what it was or how it effects...

[Mustafa]

The only reasons that I know of that cause shrimp to most are 1. they have outgrown their "skin" 2. They are stressed out in general (e.g. during transport in a bag) 3. They are reacting to toxins

Do a search on Iodine here in the forum and read up about it. It's useless for shrimp and even if some people report molting "right after I use Iodine" that does not have to be a good thing since the shrimp are probably molting as a reaction to the TOXIN that Iodine is. Iodine, although needed as a trace elements by pretty much all organisms, is a toxin in non-trace amounts. Shrimp might be more sensitive to even small doses.

In any case...I'll repeat it again here....shrimp get enough of any trace elements they need from their food (algae, fish food etc.). Iodine is a totally useless marketing gimmick.

Mustafa