Backyard Aquaponics
A place to discuss aquaponics

I put copper sulfate as fertilizer.
I didn't know copper is poison.
My plants have some symptoms of may be deficiency of some element or decease.
So I tried put some element in my system.

http://pmep.cce.cornell.edu/profiles/ex ... e-ext.html

From above: Copper sulfate is very toxic to fish. Its toxicity to fish varies with the species and the physical and chemical characteristics of the water (12). Even at recommended rates of application, this material may be poisonous to trout and other fish, especially in soft or acid waters. Its toxicity to fish generally decreases as water hardness increases. Fish eggs are more resistant than young fish fry to the toxic effects of copper sulfate (3). Very small amounts of this material can have damaging effects on fish. Permits are being required in some situations for application of copper sulfate to water bodies. Further field studies have been required by the EPA (16). Direct application of copper sulfate to water may cause a significant decrease in populations of aquatic invertebrates, plants and fish (17).

Copper is sometimes used to control algae in ponds, but those are ornamental ponds with generally a higher PH. The low PH in an AP system increase the toxicity of copper. Some of the fish stocked in AP (like trout) are also more sensitive to copper.

Obviously an extremely small amount (ppb) is not going to cause problems and the plants will take up some of it (in fact it is a micronutrient that they need) but with the increased toxicity associated with an AP system why risk using it?

OK, thanks Ao+, I understand now. Yeah, it's not good stuff. You may want to ask at a gardening shop about trace element treatments that are available and then see if anyone else on the forum has used them.


Yeah Gave, sorry - I'm aware of the aquaculture use, but the AP logic is a different - I should have phrased my question better i.e. "Why did you use it in an aquaponics system ?"

And even in aquaculture... the use of copper sulphate requires a "minor use" permit... although I thought it had actually been banned Troutman...

For general info... rainbow trout and channel catfish are known to have very low tolerance to copper, especially as fry....

Here's some info (circa 2007) from a keynote speech by Stuart Rowland... regarding treatment of Silver Perch with Copper Sulphate...



And...

Hmmm.., very interesting
Thanks you , chillidude & RupertofOZ

copper being as bad as it is..... what about brass? seems the 110 gallon stock tank has a brass fitting in the bottom......

jT

Hi All,

I have been using the Green Light Iron & Soil Acidifier in my system. It has 0.12% Chelated Copper, and 0.12% Chelated Zinc, and 3.10% Combined Sulfur with 4.60% Chelated Iron....

On the other Iron Thread, this product was deemed OK for AP, but after reading this Thread, I am wandering.
Since the middle of summer, I have used 1.3 quarts in my system. I have had several minor water losses and top ups from various causes since then. And the recent system expansion added a good amount of new water to the system too.

We recently found Gammarus Crustacean's living in the gravel in the First Blue Barrel GB, and I found them teeming in the muck on the bottom of the 2nd Fry barrel when i cleaned it out a few days ago, so it doesn't seem that this product has harmed them any.

So what do you guys think about using this product....?

Thanks
RS

My first question RS_ is, for what reason are you using it regularly ?

how many gallons of water is in your system? maybe we can calculate the % of copper in the water, and then be able to tell whether or not the concentration is dangerous. There are a lot of other factors to consider too. PH, alkalinity, period of time over which the 1.3 quarts were applied, and whether or not chelated copper is as dangerous as other sources of copper.

Maybe we need a sticky with the additives that is safe for AP.

For my system, I have not added anything at all.

Algea = cover the tank
Dirty Water = more filtration
Plant Food = seaweed extract
Sick Fish = salt bath

Wouldn't it just be far easier to say "Don't use copper". The end...full stop...etc etc.

This has been thrashed out before and with loads of respect to the newer crew go search for the info and have a good read...after all thats why it's all been left there, for you and others benifits

All good points, but I suspect there's no real need to add it anyway, other than fiddling, which many of us, including me, have been tempted into at one time or another.

He probably just added it for the chelated iron. I had a hard time sourcing chelated iron that didn't have any chelated zinc or copper. In the USA they are usually all added together in the products we have. I finally went with iron sulfate.

I didn't mean for anyone to add it on purpose, merely would find it interesting to find out his concentration level and what the various effects have been on his system.

Yeah, that's what I suspect as well. Yeah, I think you made the right choice.

Maybe chelated iron production is a business oppotunity in the US waiting to be seized !

It wasn't my intention to use copper. I was more interested in what it was doing to the fish and if there are other natural 'buffers' in the system. I guess it's a lot like heavy metal poisoning if I'm understanding what I'm reading correctly. My concern was that I'm looking for an organic food and I was looking at doing experimenting with mix of non-fish foods for more flexibility. I read about some using chicken feed but to beware of the possible copper which can some time be 'hidden'. I was wondering how to tell symptoms before the fish die which seems to be a bit less discussed.

Also, compounds react and work differently in the body (fish or human) than the base elements. I the case of salts, the ions are released into the water which is what is happening with copper sulfate and makes sense not to use. The copper proteinate and chelated copper are different (I think) and I'm still trying to figure out what they'll do or if anyone even knows. If they stay in the compound form, they may not effect the fish at all or may be broken down during digestion.