The cover must be cleaned.   This must be done on a cloudy day, in the early morning hours or after sunset. Due to evaporation of the water on the slats, mineral build-up may develop on the top surface of the slats. This can be easily removed with Aquadeck slat cleaner.   Recommendation: at least 2x per season. In an area with many trees, algae may develop in the links of the cover. This can be removed with hypochlorite (liquid chlorine). Thin this with water to a 50% solution and pour it over the entire cover with a watering can. This will cause the algae to burn inside the links.   Concentration: ROGYPAL AC-315 should be diluted in a ratio of; Regular maintenance 1 :5 Serious contamination 1: 3