YouTube VIDEO TESTS가다 100% GREEN AND SUSTAINABLE WITH ALGAEFREE더 이상 화학 물질이 없습니다ALPHA Video manage Algae Control. We put an ALPHA 2-ways ultrasound system in our water fountain. We decided to test our system for 4 weeks to see the difference of the water quality. Link to see video no 1:https://youtu.be/63BFTaqDQ8QThe water was DARK GREEN the difference.Link to see video no 2:https://youtu.be/2addAnj8ifc Results after 4 weeksThe water was totally clear!After Ultrasound kill the algae, the membrane and algae die, then sink and fall to the bottom like this. (see above pic)See YouTube videos for 7 recreational boat results.https://youtu.be/zJrKT8_1Z3s