Envirosonic - Model ES-150 ES-150 - Ultrasound Unit
This unit is designed to control algae in small lakes and ponds, irrigation tanks, water storage tanks and reservoirs. It will perform similar functions to the ES-300 over a smaller area of approximately 15 hectares. It is easily powered by solar panel systems and controls blue green algae very well.
- In swimming pools it can reduce the use of Chlorine by up to 80%
- In open lakes, reservoirs and canals it will control all algae and reduce diatom blooms, reducing pH and improving water quality for discharge consents
- In irrigation systems it will clean pipes and nozzles, reduce pH and clean greenhouse hard surfaces
- In cooling towers it will remove scaling, reduce pH and control bacteria and algae on surfaces, reducing management costs and improving water quality
It is constructed of 316T stainless steel and titanium and is powered by 240V AC, 110V AC or 24V DC (with solar power systems). There is a lifetime guarantee on the transducer and five years guarantee on the electronic
Research work, undertaken at the Centre for Aquatic Plant Management, showed that exposure of Spirogyra and Scenedesmus to ultrasound for less than a week induced changes in the algal cells. The interior of the cell shrunk away from cell wall and the cells died. Measurements of chlorophyll content of cells also declined, and exposed cells did not regrow after 3 weeks exposure. In outdoor pond tests, algal growth was much lower than in tanks without any treatment, and there were no effects on Daphnia, an invertebrate used as a test organism. Fish are not effected because the sound level produced is half the required decibels to effect fish. They do not affect submerged plants, water lilies or other desirable aquatic plants, and are highly specific to algae.
The pictures below show examples of how algae respond to exposure to ultrasound. The filamentous alga is Spirogyra exposed to treatment with an Aquanet device in glasshouse conditions for a period of 21 days. The disintegration of the cell is clear, even after 7 days. This is due to functional membrane changes in the cell induced by ultrasound. The unicellular algae is Scenedesmus. This species show characteristic banding of the cytoplasm when exposed to ultrasound for 3 days.
The graph shows the growth rate of exposed (pink) and untreated (blue) algae after exposure to ultrasound for three weeks. This shows that permanent damage has been caused by only a brief exposure. Continued exposure will eradicate all algae except algae that swim and move, so called motile algae, but the invertebrates and fish must have something left to feed on, and this is the key to the environmentally friendly nature of ultrasound treatment - it does not kill all algae, it reduces the numbers of nuisance algae and the biomass of filamentous algae to point where balance with other algae and organisms is restored