Molly, it is correct that this may be a sign of mineral deposits from a leaking line. We would be happy to take a closer look to provide a more detailed diagnosis of your water heater. You can give us a call at any time at (215) 866-4391 and we would be happy to answer any question or schedule a visit.
It could be mineral deposits from the water line leaking water... I would get it checked out by a plumber such as Horizion Services... I've always had great dealings with them !
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