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water: high iron and copper

8.5K views 16 replies 8 participants last post by  Diana K  
#1 ·
After we had our well drilled at our place in Virginia (25 years ago), I had the water tested (for free) at a local plumbing supply place. Though I forget the details, it turned out to be very soft, somewhat acidic, but very high in iron and especially copper. When he gave me the results, the guy at the plumbing supply place said, if the metals were any higher, the water would not be fit for human consumption. Indeed, the toilet tanks and bowls can be orange-brown with precipitated iron, and the ice cubes leave a light green copper residue when they sublimate away. I have never kept fish there; grew some plants emerse in rainwater, soil, and a little manure. In other words, the well water is no good for fishes or plants, especially crypts.

Of course, there are other sources of water: rainwater or the Hazel River, which borders the property. But I fear, based on past experience, that I am simply not going to the trouble of dosing rainwater to restore minerals or hauling river water up the hill to do water changes. In fact, using a python to do water changes is about as ambitious as I am likely to get. (I have now discovered the Walstadt method here, but even that requires some water changes, and i would probably want to do high light and CO2, which I already have.)

I have an old reverse osmosis unit that I used a lot when I lived in Austria ten and more years ago, but I was not paying for the city water it took to produce the flow from that unit. Also, I ascribe some of my lack of success/indifferent success with the plants at that time to my failure to consistently and accurately re-mineralize the ro water.

What I would really like is some simple way to de-toxify the well water with some kind of whole-house solution -- at a reasonable cost. I could be wrong, but I have the impression that the typical home water treatment system (with salt exchange) does not produce good water for aquarium fish or plants. A whole-house ro system is probably too expensive both to buy and to run (wastewater). Are there any new technologies out there that might do the trick? Have any of the experts on here had to deal with similarly unsuitable domestic water?

I retired about a month ago and came here to Switzerland to spend the time with my wife (and read these fora) until she finishes her assignment and she too retires later this year. When we return to the United States, I hope to return to the hobby -- fish are easy, planted tanks hard -- with the knowledge gained on this fabulous site and a few other like it.
 
#2 ·
Iron in the water shouldn't be a problem... it precipitates out pretty quickly, and the plants use it anyway. I'm not sure how high the copper levels are in your water, but I dealt with 3ppm copper for many years. While there were some pants that didn't tolerate it, MANY did fine with it, including most Crypts. I grew nicer Crypts during that period than any time since then. It was a serious problem for some fish, especially Rainbows, and, of course, all inverts... Snails died on contact with the water.

Unless your copper level is a lot higher than that, I'd say work with what you have. Most people do much better keeping up with regular water changes and learning what plants do well in their local water supply than trying to change the water into something else.
 
#3 ·
Karen - Thanks so much for taking the trouble to respond. I'l need to have a certified laboratory test the water again, of course, but I'm thinking that, if the guy said it was barely acceptable for human consumption, the copper may be over 3 ppm. If a faucet drips, it leaves a bright green stain on the basin in no time.

Any idea where can I find information on the safe levels of copper for given species of fishes and plants?
 
#5 ·
Thanks for that. At the time, pre-internet really, I couldn't find any information on levels of toxicity. my kids were small, and even the pediatrician didn't know. His answer was "The towns monitor that stuff, so it's probably OK"!

But it felt wrong to give something to my kids that killed other organisms so quickly. I'm glad that I chose to use bottled water for drinking water during that period. OTOH, I did have very successful planted tanks during that period, I just avoided the plants and fish that didn't do well in my water.

Oh, and yes, our toilets, sinks and bathtub were perpetually green!
 
#6 ·
I googled: 'cryptocorynes "high copper" in water'.

One of the first items to come up was what appeared to be several pages on the subject of metal toxicity (to fishes and plants) drawn from from Walstadt's book. (The site where it appears is Russian: "tvaya knizhnaya polka" = your bookshelf.) The research that Walstadt cites here gives a rather alarming picture of toxic effects at fairly low concentrations of heavy metals, including iron and copper.

For copper: "Copper Brook Trout Juvenile mortality safe level: 0.010-0.017 ppm"

On plants, the article/citation says: "Metal Toxicity in Plants

Plants afflicted with metal toxicity exhibit various symptoms that might be interpreted in*correctly as nutrient deficiencies. Symptoms of aluminum toxicity for Vallisneria are

premature browning and senescence of leaf tips [22], Excesses of copper, manganese, and zinc may induce iron deficiency and chlorosis [23],

Iron toxicity has been studied in at least two aquatic plant species. Thus, investigators [24] reported a 75% growth reduction in the pondweed Potamogeton pectinatus as a conse*quence of adding iron (1.2 mg FeCU/g) to the substrate. The leaves turned brown, and the roots became pale or red brown and did not reach the bottom of the pots in which they were planted. Hydrilla verticillata, exposed to well water containing 1.2 ppm Fe, became covered with a rusty brown color and began to decay [25],

Q. I added iron (as FeCl3) to my tank to reduce phosphates in the water. (Phosphate reacts with iron to form insoluble iron phosphate.) Six days afterwards, the phosphate concentration had decreased from 0.6 ppm to 0.1 ppm, but I began to see phosphate deficiency in some of my plants. It started with the slower growing plants. For example, the Cryptocoryne had brown spots on their leaves, which expanded until the whole leaf was affected. Fast-growing plants spe*cies seemed unaffected by the P deficiency, which surprised me, as these plants usually require more nutrients.

A. I think you're confusing phosphate deficiency with iron toxicity. Phosphate levels of 0.1 ppm in the water are more than sufficient for plant growth. The brown spotting of the leaves suggests iron toxicity. The browning is due to iron deposits in the leaves, as the plant tries to store the excessive iron coming in.

The fact that your faster growing plants did not show the 'deficiency' supports my conten*tion that the problem is metal toxicity not nutrient deficiency. Metal toxicity in plants can be overcome by rapid growth. Faster growing plants 'dilute out' the problem; metal concentrations within the tissues decreases with new growth. Slow-growing plants are at a disadvantage; the metal concentration within the plant builds up to injurious levels."

Any thoughts?
 
#8 ·
I know there are some inserts for aquarium filters that will reduce copper levels, and other mineral levels.
They have names like
Phos-zorb
Cupri-zorb
and so on.
Some of these are available on sponges, others are loose media and would need a bag. I do not know how these work.
I am not sure if similar materials are economical for larger volumes of water.

http://www.bigalspets.com/cuprisorb-250-ml.html

Another method of removing heavy metals is via chelation. There are aquarium products specifically for that. Scroll down to E.D.T.A.

http://www.nationalfishpharm.com/products.html
 
#9 ·
Just to put toxicity in perspective. Most experiments are done with salmon or trout because those are some of the most sensitive species. Way more sensitive than our average fish. Second, with all chelators added via fertilizers the toxicity in our tanks is a 1000 fold lower.
 
#10 ·
The lethal dose 50 (LD50) for duckweed is 0.15 ppm copper. Many other plants are killed around this concentration. A normal Cu level should be 0.015 no higher.

I don't think that study with FeCu is reliable for seeing Fe toxicity. If they were adding copper then it would kill the plants first, not the Fe. Also, people routinely off over 1 ppm Fe to their tanks in the hobby without problems.

And yes as Yo-han said chelation tends to make the nutrient less toxic than non chelated chemicals.
 
#11 ·
Humic substances in the tank (decomposed organic matter, like leaves and roots, but very finely composted) also act like chelators.

This may very well be an example where the fewer water changes the better! That means less copper enters the tank from the well water.
 
#13 ·
I agree- the less stuff that gets into the tank to begin with then the less it has to deal with. This leaves more of a safety cushion for other possible problems that could crop up.
If there is a way to avoid adding the copper to the tank in the first place that is the way I would go.
 
#14 ·
How about we use RO water for aquatic plants and for human consumption, but use city supplied water for everything else like washing, cleaning, toilets, showers? I have a small RO unit installed, and I'm trying to justify its wastewater cost by using it for as many things as I can around the house.

Now to my question: for my low tech planted tank, with a good substrate like UP Aqua's "Aqua Sand", if I just add some oyster shells, and use only RO water, will that work? Or will it lack many minerals?
 
#15 ·
I think it is more controllable (and only a little bit more expensive) if you remineralize the water before adding it to your tank.
 
#16 ·
They make a catylist bases iron remover. its zeolite treated with something ( I want to say PP but its been awhile) its a green sand. it oxidizes the desolved iron so it can be removed mechancially. It is not a 100% removal, but it gets alot, sending it thru many times might be a viable option.
 
#17 ·
We had RO set up the way you describe. The whole house was on a filter that was more like the traditional sodium exchange water softener (it was actually something else) and the RO was just at the kitchen sink.

I would roll a garbage can into the kitchen (Rubbermaid Brute on wheels) and fill it with RO. Then spread it out to the other garbage cans and blend with tap water.
My tap water was not so bad, just a bit hard for certain fish.