I guess it depends on the type of quakes you get too. A slow roller like you isn't so bad but get a nice bumpy one near a fault and look out. Every area can get earthquakes. People around here would say we don't have earthquakes but they do happen. We have 'em hit NJ every 10 years or so. They're only around a 2 or so and most people just think a big garbage truck rolled by or if they were driving didn't even know that one had happened. So nothing to do about a tank here and I wouldn't have the foggiest idea of what to do to prevent a catastrophic tank failure in an earthquake prone zone but I'd be sure to have some plastic tubs, extra heaters, filters and air pumps handy.
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