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1. Control the operating current: Generally, the operating current is lower than the limit current. 2. Electrode reversal: This can effectively reduce scale on the membrane and cathode. Scale usually accumulates on the cathode surface of the concentrated water chamber; by reversing the electrodes, the concentrated water chamber and the fresh water chamber are also reversed, thereby disrupting the stable formation of scale and thus reducing its accumulation. 3. Acid cleaning: This is an effective method for removing deposits. When scale accumulates to a certain extent, acid cleaning is necessary. The frequency of acid cleaning depends on the rate at which the desalination efficiency declines; it is usually carried out once every 1–4 weeks. Hydrochloric acid is commonly used, with a concentration of 1–2% – a higher concentration should be avoided as it can damage the ion exchange membrane. Acid cleaning is typically done through a cyclic process, involving cleaning the concentrated water, dilute water, and fresh water chambers all at once. The pickling time is generally 1–2 hours, or until the pH value of the pickling solution near the electrodialyzer remains unchanged. After pickling, rinse with clean water until the pH of the inlet and outlet water is equal. For calcium sulfate precipitates, they can be cleaned first with a 10% sodium carbonate solution before pickling. 4. Alkaline cleaning: Acid cleaning cannot remove organic precipitates; for such types of contamination, alkaline saline solution can be used to eliminate the organic substances. The alkaline cleaning solution is typically composed of 9% NaCl (refined salt is preferred) and NaOH. The cleaning process lasts for 30–90 minutes, after which the surface should be rinsed with clean water until it is free from contaminants. Alkali cleaning can be carried out using the acid cleaning system; generally, no separate equipment is required. 5. Regular disassembly and cleaning: When the desalination rate cannot be restored using the methods mentioned above, the EDI membrane stack should be disassembled for cleaning and reassembled. Generally, electrodialysis requires disassembly and cleaning every 1–1.5 years.