They weren't rocking too badly, fortunately. But, do you think about how secure your tank is, when you set it up in our earthquake-prone region? I think about that. My tanks are not strapped to the wall, but I've located them so they're not near places where people are likely to be, not next to the sofa or tv or a play area. I think I should probably put some wood along the edges of the counter, to keep them from sliding forward. During the Seattle quake a few years ago, the computer monitor on the desk slid forward almost into my son's lap. (We grabbed it before it hit)
Something to think about.
BC building codes make any new installation of a hot water tank be secured to a wall securely.It makes sense that should apply to tanks of all types just for safety.
I think when I set up my next tank I am going to secure the stand for sure.
I already secured the TV in my sons room since it sits up high.
Something to think about for sure. Most seismologists say its just a matter of time for us.