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Coptrol Algicide Questions Answered

How does it work, Is it safe to use.

Application rates and More

What types of algae will it control? Algae Crop

Generally speaking all free floating and filamentous green algae including brown slime.

Will it affect livestock, birds and fish?

When used in accordance with the label directions, Coptrol will not harm livestock, birds or fish.

How does it work?

Algae seek out Coptrol for its nutrient value and absorbs it through their cell wall. Digestive enzymes within the

cell break down the compound and release copper within

the cell to kill algae.

How effective is Coptrol?

Coptrol kills algae and nothing else. It is a copper miser,

when compared with copper sulphate (bluestone) it uses

one fifth to one eighth of the amount required if copper

sulphate was used and achieves a better result. Results

are apparent soon after application. When used as directed

it does not harm humans, fish, stock, wildlife, plants,

pastures or turf.

Coptrol will not control aquatic weeds.

How safe is it?

It is completely safe when used in human drinking water.

See a word of caution later in these notes concerning blue

-green algal blooms. There is no risk to domestic animals

where Coptrol is used in farm impoundments. It will not

corrode metal surfaces such as water tanks, irrigation

equipment, spray valves and pumps.

It is not corrosive to aircraft and aircraft equipment. It

will not build up in the soil.

Coptrol is specific to algae in water and should not be used

for aquatic weed control.

It will not harm rice,hydronic plants,golf greens. No withholding

period is required when used as directed.

How is Coptrol applied?

Coptrol is easy to apply. First, measure and dilute the

required amount of Coptrol in about one in ten in water,

then apply evenly over the surface of the water being treated.

Coptrol may be applied from aircraft, from boats or can be

sprayed from the banks of larger storages. It may be dripped

direct into flowing water in high volume treatments such as

flood irrigation water.

Click here for application rates.

How does Coptrol compare with bluestone?

Chelated *copper the "active ingredient" of Coptrol has been shown to be more effective than copper sulphate in the control of algae. Its advantages are:

Lower concentrations of copper are required for the

same result.

Application rates are less critical.

Copper persistence in the water at algitoxic levels is

longer.

Treated water medicated with Coptrol can be used for

irrigation and drinking water. Water treated with

bluestone can not be used in irrigation or drinking water.

Copper Sulphate/Bluestone

1. Precipitates very quickly - Copper sulphate is precipitated by carbonate hardness, accumulating in sediment at the bottom of the storage and rendered unavailable to control algae. In normal water the free copper ions which are toxic to algae combine rapidly with the carbonate ions and fall to the bottom as insoluble copper compounds within an hour. Chelated copper (Coptrol) is stable in hard water and remains available to be absorbed from the water by algae.

2. is difficult to apply - Bluestone irritates the eyes and skin, is very corrosive to equipment, is invasive in aircraft instruments and is hard to spread evenly from the air.

3. is affected by humic content - The greater the humic content in the water, the quicker copper is tied up and precipitated out. Decomposing plant matter is thus a major limiting factor in getting results from bluestone.

4. contributes to livestock toxicity problems - Because so much copper from bluestone precipitates out rapidly as insoluble carbonates and hydroxides, copper build-up in the soil and pastures is a continuing problem. Copper toxicity in sheep grazing on sub clover, or where Heliotrope or Paterson's curse is present is well known in the irrigation areas.

Unlike copper sulphate, chelated* copper is not precipitated by carbonate hardness and is dissociated to release more copper as it is absorbed from the water by algae.

*(Chelation is a process which chemically binds metal ions to other molecules - known as chelating agents - making the final compound very stable).

Can Coptrol be used in conjunction with farm animals?

In normal circumstances, use of coptrol to treat water,dams or waterways

will not present a toxicity problem. On the contrary,copper deficiency in

pastures grazed with sheep and cattle in large areas of NSW, Australia has

been a persistant problem for many years. Hungerford (1975) stated that

animals grazing from a pasture which contains less than 4 ppm of copper

will certainly suffer copper deficiency. He further suggest that the popular

copper sulphate worm drench of earlier years may have masked the

inherent copper deficiency over wide areas of pasture in NSW.

Word of caution: Blue-green algal blooms happen when there are high nutrient

level, low flows in rivers, low wind and high temperatures. The main cause

of concern about blue-green algae is the ability to produce highly potent

toxins. The toxins produced can persist in water for weeks.

In Australia no recorded human deaths have been attributed to blue-green

algal blooms. The best documented case of human deaths occured in Brazil,

where around 75 dialysis patients died after direct exposure to toxins in

their dialysis fluid. However, many stock deaths have been documented.

The first scientifically documented case of an algal bloom causing deaths

was in South Australia's lake Alexandria in 1878, where cattle, pigs and

sheep died within hours of drinking contaminated water. The toxins

produced persist in water for weeks. The toxins can also be concentrated

by shellfish, which poses a potnetial health risk if they are consumed.

Click here for further information on blue green algae.

Extreme diligence should be excercised when treating potable water

supplies which are heavily infested. As each water storage is unique

it is recommended to obtain and rely on specific independent advice.

Treatment of algal blooms with Coptrol will cause the dead algae to release the neurotoxins into the water immediately. These toxins may present a hazard to livestock immediately upon treatment and for a further period of about 28 days. The degree of risk depends on the type of algae present, the level of infestation and the time taken for aquatic bacteria to detoxify the toxins.

However, if the treatment is not undertaken the algae will continue

to bloom, releasing increasing amounts of toxin into the stock water

supply with inevitable results. When Coptrol treatment finally occurs

the released toxins will be present in the water at much higher rates

and for much longer periods. It is best to treat algal blooms early

and to exclude livestock for at least 28 days.

Click here for Blue-green algae safety check list.

What about Ragwort toxicity?

The alkaloid in Ragwort weed (Seneca jacobaea) , which is toxic to horses and cattle, does not affect sheep which often graze on the weed. However, the Ragwort alkaloid reduces sheeps' ability to excrete copper and thus Coptrol should not be used in water sources where sheep are grazing on Ragwort.

Can Coptrol be used in fish ponds?

Water treated with Coptrol at a level of 1 ppm elemental Cu

(copper) does not result in a significant copper residue

problem for fish. Chelated copper compounds, especially

Coptrol, are highly specific to algae and have been shown

to present a minimum hazard to fish.

USEFUL HINT: Decomposing algae treated with Coptrol may

lead to oxygen depletion of the water. Lack of oxygen may

cause fish to suffocate. Therefore, in bodies of water containing

fish, it is best to kill algae slowly. It is recommended to treat

only one third of the area, then wait 10 days to allow the oxygen

level to build up again. Then, resume the treatment beginning

from the shore and moving outwards in bands to avoid trapping

fish in treated areas.

Click here for Coptrol use in Aquaculture.

Can water treated with Coptrol be used for irrigation?

Water treated with Coptrol at copper levels of 0.2 ppm to

1.0 ppm presents no hazard when

used for watering or irrigating

green pastures or crops. Copper as a micro-nutrient is frequently included in all-purpose fertilizers. Copper is also used liberally in horticultural pesticide formulations, such as copper oxychloride and Bordeaux mixture.

Is it safe to swim in water treated with Coptrol?

Yes, swimming, fishing,(except in blue-green algae infestations) and other recreational activities will not be inhibited by treatment of the water with Coptrol.

What about dogs, cats and other pets?

When Coptrol is used at rates authorised on the label, it will not present any hazard to companion animals. What humans can drink, pets can also.

How long will Coptrol last?

The active life will depend on the level of algae present at

time of treatment. Coptrol is only removed from treated water

when it is killing algae. Algae seek out Coptrol for its nutrient

value and absorb it into their cell wall. Digestive enzymes within

the cell break down the compound and release the copper within

the cell to kill algae.

Copper persistence in the water at algitoxic levels is longer than

with old-fashioned inorganic copper compounds such as bluestone.

Will I need more than one application?

Generally speaking, no. Used at the correct rate, Coptrol will control

most infestations in a single treatment.

However, there are a number of situations where more than one

treatment is advisable. In bodies of water containing fish, it is best to

kill algae slowly. It is recommended to treat only one third of the area,

then wait 10 days to allow the oxygen level to build up again. In

particularly heavy infestations of mixed algae, a second treatment after

10 -15 days may prove useful to ensure clean sparkling water results.

Can Coptrol be used in drinking water tanks?

The three components of Coptrol are specifically exempted from the

schedules of the *NHMRC Uniform Poisons Standard.

Coptrol can be used in all water for human consumption.

However, if the water tank is sealed from sunlight algae cannot

grow and treatment with Coptrol is unnecessary.

*National Health and Medicine Research Council of Australia.

Will it work in winter?

Yes, Coptrol can be used at any time of the year, providing water

temperature does not fall below 16°C.

How can I apply it?

Because it is a highly soluble liquid Coptrol is really easy to apply.

For general application to farm dams/ponds, simply dilute 1:10 to 1:20

with water and spray evenly over the surface from aircraft, from boats

or pontoons, from the banks of smaller storages or even dripped directly

into flowing water.

Why is Coptrol so effective in rice crops?

Algae, or slime, is a perpetual problem in rice crops in Australia and in

other parts of the world. In some years there is so much algae in the

water that great slabs lie all over the surface smothering the emerging

crop.

Coptrol offers a new approach in the Prevention and control of free floating

and filamentous algae in rice.

Far from being irritant and invasive, it is extremely adaptable in application.

It can:

Piggyback on herbicide and insecticides flown on to

aerially sown and drill sown crops.

Be mixed with water and dripped in to water flowing into

bays.

Be poured from banks directly into flooded bays.

When using Coptrol in a tank mix with chlorpyrifos RCI Compatibility Agent should be added at the rate of 1 % of the total volume of mix. This protects the two products from reacting with each other. And allows growers the opportunity of flying both Coptrol and the insecticide on together.