Are fears of our tap water unfounded? For example, water entering DC WASA's distribution system averaged 3.3 ppm of Copper in 2008. The EPA's action level for Copper in drinking water is 1.3 ppm and tap water levels in DC are around 0.1 ppm on average. I'm having problems growing Val's. but my RCS seam unaffected.
Tap Water
- Thread starter Tug
- Start date
So I was about to give up on searching, when I found this:
Chemical Toxicity Studies on All Organism Groups Chemical Toxicity Studies
More relevantly, check under the inorganic copper levels listed here:
Water celery (Vallisneria spiralis) Chemical Toxicity Studies
It seems you're dealing with one study calling an average around 1.6mg, while another calls .1mg to 5mg (probably testing with varying levels of CaCO3, temp and pH which changes toxicity levels) which discounts your tap water as being toxic to vals for the most part.
Looking over here:
Ecotoxicity Summaries by Species
We see a listing for Neocaridina denticulata (cherry shrimp) that, according to the EPA looks more like around .37mg. There is also a listing for, more broadly, Caridina spp. in general at around twice that rate.
So then, it appears more likely that your vals would die before your shrimp. The exception I can see would be as mentioned above; variances in other parameters effecting toxicity.
Hope this helps some.
-Philosophos
Chemical Toxicity Studies on All Organism Groups Chemical Toxicity Studies
More relevantly, check under the inorganic copper levels listed here:
Water celery (Vallisneria spiralis) Chemical Toxicity Studies
It seems you're dealing with one study calling an average around 1.6mg, while another calls .1mg to 5mg (probably testing with varying levels of CaCO3, temp and pH which changes toxicity levels) which discounts your tap water as being toxic to vals for the most part.
Looking over here:
Ecotoxicity Summaries by Species
We see a listing for Neocaridina denticulata (cherry shrimp) that, according to the EPA looks more like around .37mg. There is also a listing for, more broadly, Caridina spp. in general at around twice that rate.
So then, it appears more likely that your vals would die before your shrimp. The exception I can see would be as mentioned above; variances in other parameters effecting toxicity.
Hope this helps some.
-Philosophos
Thanks Philosophos. As always, you back up a thoughtful response. Is .37mg the same as ppm? There is a lot of fear mongering about caring for RCS, but I find them to be extremely hardy and prolific. What about food for shrimp with added Copper for blood formation? What is that about? Should we feed our shrimp food that has Copper in it?
Most invertebrae use hemocyanine to transport oxygen. Unlike Hemoglobin, it is formed by copper instead of iron. So, yes, they do need copper to oxygenate their tissues, but I doubt they do need it as addons. It is in the traces form and suerely enough provided by your tap water or planted tanks ferts we use
As far as temp, they can withstand brief exposure to higher than 80-81F.
I think this is the limit for long term survival(79-80F).
For breeding, 78F or so seems better in terms of production or lower.
I had some lower grades exposed over several weeks at set temps and found the the lethal temp curves for my CRS's.
70-75F seems pretty good.
RCS are very tolerant by comparison.
As far as copper and other nutrients, they get this from their food, there's no need to add Iodine and copper to the water, you can if you want, but they need this like we do, as food, we do not soak in our nutrients via the skin
We get it from our food, shrimp may be able to do both, but if it's in the food, they have plenty
That seems pretty high in Copper just the same.
You can get those metal removal filters for th whole house or just for the tap and the aquarium.
Fairly cheap and activated carbon also might be wise as it will nab a fair amount of organics and offer good taste also.
Would not hurt and you will like the taste better. Also, change every 3 months for the carbon. No need for a RO filter.
Regards,
Tom Barr
I think this is the limit for long term survival(79-80F).
For breeding, 78F or so seems better in terms of production or lower.
I had some lower grades exposed over several weeks at set temps and found the the lethal temp curves for my CRS's.
70-75F seems pretty good.
RCS are very tolerant by comparison.
As far as copper and other nutrients, they get this from their food, there's no need to add Iodine and copper to the water, you can if you want, but they need this like we do, as food, we do not soak in our nutrients via the skin
We get it from our food, shrimp may be able to do both, but if it's in the food, they have plenty
That seems pretty high in Copper just the same.
You can get those metal removal filters for th whole house or just for the tap and the aquarium.
Fairly cheap and activated carbon also might be wise as it will nab a fair amount of organics and offer good taste also.
Would not hurt and you will like the taste better. Also, change every 3 months for the carbon. No need for a RO filter.
Regards,
Tom Barr
Sorry about that, it's mg as in mg/l which is the same as ppm.
If you compare other LC50's, shrimp actually have a lower tolerance than many fish. I'm fairly sure shrimp maintain osmotic balance in the same way as fish, which means that they'll ingest water to maintain it. If this is the case, then they'll be sucking in Cu not only if it's in the food, but also in the column.
-Philosophos
If you compare other LC50's, shrimp actually have a lower tolerance than many fish. I'm fairly sure shrimp maintain osmotic balance in the same way as fish, which means that they'll ingest water to maintain it. If this is the case, then they'll be sucking in Cu not only if it's in the food, but also in the column.
-Philosophos
Great! So, iodide in my tap water averages 27 ppb. Is iodide the same as iodine? If iodine facilitates calcium uptake and successful molting for crustaceans, would adding something like Kent marine iodine be needed? What is 27 ppb in mg/l?
Oops, sry Tom didn't see that you already mentioned iodine.
Tom Barr;39185 said:As far as copper and other nutrients, they get this from their food, there's no need to add Iodine and copper to the water, you can if you want, but they need this like we do, as food, we do not soak in our nutrients via the skin
We get it from our food, shrimp may be able to do both, but if it's in the food, they have plenty
Regards,
Tom Barr