How to use Coptrol to kill Algae in Waterways and Irrigation Channels

Algae in irrigation channels a persistent problem!

There are more than 17000 kilometres of earthen irrigation channels in Australia all with varying amounts of plant life and weed growth on the banks and in the water way. Decayed vegetation from nearby trees and decayed foliage from the channel banks as well as the run off from adjacent

farms provides plenty of aquatic nutrients. When combined with

abundant sunlight and high summer temperatures, blooms of algae

are a frequent occurrence.

Algae and Algal blooms

There is no easy definition of an alga. Algae are generally

microscopic organisms, are generally thought of as simple aquatic

plants which do not have roots, stems or leaves and have primitive

methods of reproduction.

For further information see our Algae.info website.

Algae can impede water flow, create an environmental nuisance and may even be toxic to humans and stock. Successful eradication of algae depends on the correct identification of the species, and the use of an algaecide that does not harm aquatic animals, livestock, plants, humans, and is specific to algae and no other plant life.

Coptrol use in farm dams banner - waterways

Coptrol is a chelated copper compound with a low level of toxicity. Its unique ability to kill algae is because algae actively seek out Coptrol for its nutrient value and they absorb it throught their cell walls. Digestive enzymes within the algae cell break down Coptrol which releases the copper held inside the chelate. Because the algae cells gradually accumulate Coptrol, there is not an immediate toxic effect on algal cells. Generally it takes between 36 to 48 hours for results to become apparent. This rate of deterioration is dependent on the dose rate used and level of algal concentration at the time of application.

What are the dosing options?

Dosage rates depend on a number of factors including water

volume, flow rates, algal concentration and dosage methods.

There are three practical options available: Coptrol easy to apply - waterways

Single dose point
Multiple dose point
Drip/spray application

RCI does not recommend the use of Coptrol if the single dose option is chosen.

Multi dose point method

The multi point method is used when there are relatively

rapid flow rates of water. Subject to being able to apply the

product in a uniform and reliable manner, the rate of application

should be 2ml per 1000L (cubic metre) of water continuously for

48-36 hours.

It should be noted each system has different characteristics which

may influence the efficiency of this dosage recommendation. For

example undertaking multi point dosing after the accumulation of

high levels of algae have occurred will significantly reduce the

effectiveness of this type of application and may require higher

application rates over a longer period.

Drip/Spray

This method is dependent on the ability of the operator to be able

to pass sufficient Coptrol over the surface of the water in the channel.

This approach is only feasible with either a static or slow moving

channel system and requires the operator to be able to apply Coptrol

evenly over the surface of a channel. In our experience this system

is more cost effective and reliable than the multi point dose method

and can be used to prevent and treat problem algal developments.

The suggested rate of application in this situation is 5ml per 1000L

(cubic metre)of water. This will require a minimum of 48-36 hours

contact time. In extreme conditions rates can be increased to 10ml

per 1000L (cubic metre) of water.

Recommended dose rates

If algae is a problem in a waterway or irrigation chanel follow this 5 step method to keep your waters clear and bright.

1. First identify the algae present. If you are not certain visit

www.algae.info. This site enables you to identify all the common

algae in Australia.

2. Now calculate the volume of water to treat. Ignore depths below 1

metre. We have a page which explains the methods used to

determine the amount of water to treat. if you need assistance see

How to calculate the volume of water to treat with Coptrol.

3. Next calculate the amount of Coptrol needed. An easy way to

calculate is:

a) If you are using the multi dose point application.

• Use 2 mL of Coptrol per 1000 Litres (1 cubic metre) of water. That is equivalent to 2 Litres of Coptrol per 1000 square metres of surface area continue the application without interruption for 48 hours.

b) If you are using the Drip Spray application

• Use 5 mL of Coptrol per 1000 litres of water (1 cubic

metre) or 5 Litres per megalitre of water. In extreme

conditions the rate may be increased to 10 mL per cubic

metre of water. Continue the application without

interruption for 48 hours.

4. Dilute the required amount of Coptrol using a 1:10 or even a 1:20
Coptrol water dilution.

5. The best application method is by spraying. Apply on a sunlit wind

free day when algae first appear. If this is impractical look at our

general recommendations.

6. If you still need help call us at no cost to you. Contact us

where our free call numbers are displayed.