@sebestyen tiberiu Your mirror idea would be too expensive, each of those balls cost 40 cents, at 6.5 million balls for both Ivanhoe and Elysium that's 2.6 Million. Ivanhoe and Elysian reservoirs will be blanketed by about 3 million balls each for about four years. They will be removed when a covered replacement reservoir is built near Griffith Park's Travel Town area.
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