Pennies for your thoughts

[HARO]

Back in the early seventies I was interviewing an older aquarist for our local club's publication. He mentioned that he always placed a few pennies in his tanks to keep down the algae and he believed it helped to fight off parasites as well. Then, about ten years ago I started to help out at the garden center where I still work part-time in the water garden/pond section. We have about a 500 gallon display pond in the entry area, and kids like to toss pennies in there (as well as a lot of other things). I fish out most of the coins, but always leave about 40 or 50 in there. The pond is in a greenhouse, gets full sun from morning 'till 6:00 or so, is over-populated and over-fed, and yet there is never a shred of algae in it! Also, the fish have never been sick, and we have only lost one. (Pump failure- our 20" koi succumbed.) Has anyone else tried this? And what are your oppinions on the practice? John

 

[ididntdoit99]

Copper sulfate is used in swimming pools to stop algae growth, but is the copper good for your fish? I've heard it isn't, but on my little filter/fountain I made the water runs out of a copper tube. No ill effects yet, and i can say my water is clearer, but i'd say that is from the filter media in the tank, probably not the copper tube it runs through.

 

[HARO]

I had an elderly gentleman come in a couple of years ago asking about his algae problem and how to fix it. I explained about plants, filtration, barley, and so on. Then he said "I wish I knew where I could get some copper sulphate. We used it long ago and it really works!" I sold him a small bag of it after making him promise that he would't come back to give me hell if it backfired. Haven't seen him since, so I don't know how things turned out. John

 

[ididntdoit99]

Well if you leave a penny in water it will break down.. so i'd assume its the same as dumping in some copper sulphate. If you can find some pennies dated 1982 or earlier, they are 95% copper. If they are 83 or later, they will work for a while until the copper breaks down and you have nothing left but a zinc penny.

 

[addy1]

I have heard that trapdoor snails die if you put copper into the pond. So if you have trapdoors be careful

 

[fishin4cars]

Copper will kill any invertabrae, I know copper sulfate is used in pools for algae control and in some cases as a treatment in salt water fish and fresh water fish, But I have heard too that there can be long term effects form long term exposure to copper. Now what those effects are, I really don't know but I'm sure constant exposure can't be really good for the fish.

 

[pinon ponder]

Here's an article I found with a quick google search. I don't think it's worth the risk, especially when it's so simple to keep things clean and clear with good filtration.
http://edis.ifas.ufl.edu/fa008

 

[KennethO]

I think it also depends on the water. Soft or acidic will leach more than hard alkaline water like what most fish are in. The harder water will cause minerals to collect on it instead.

 

[HARO]

Thanks, Pinon Ponder; Very informative. John

 

[DrDave]

I refer people to that site often for salt treatment. I have a link on one of my web pages to the one on salt.