We just pumped out our nickel tank for it’s six-month cleaning and have found a couple of inches of crystalline material in the bottom of the tank. We use a Watt’s nickel bath that is continuously filtered. What is this? L. F.
The crystalline material is most likely boric acid. Boric acid has a concentration of approximately four oz/gal in cold baths and tends to drop out of solution fairly readily. I assume that the temperature of the bath is allows to drop over the weekend or when not in use. When you bring the plating bath back up to operating temperature the boric acid is slow to redissolve. To verify this send a sample of the crystalline material out for analysis.
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