Our company reclaims water and uses an electorcoagulation cell. The reaction chamber is filled with 100 square feet of aluminum plates. The influent passes vertically between the stacked plates while dc electricity is passing through the plate stack on the x axis. Aluminum hydroxide is accumulating on the plates and insulating them. The hydroxide film is also not allowing the cleaning solution (sulphuric acid) to penetrate to the underlying aluminum oxide layer when the plate stack is cleaned after a batch run. The dc current direction is reversed every 15 seconds. MY QUESTION: Is there any compound which would solvent this hydroxide/oxide slime. The deposit is @10thousands deep/and when scraped is somewhat viscous. Thanks in advance for any help.