sera KH/pH Plus (Alkaline Buffer)Sinking pH levels are dangerous and common in the UAE due to low KH levels of the local tap water. This product is essential for UAE keepers of our Discus. ae fish to maintain neutral pH levels, helps avoid acidic soft water which can harm many of the species we supply. This includes our Stendker discus fish which are not conditioned to live in soft water. sera KH pH Plus provides additional stability and safety in the aquarium: Buffers and stabilizes