When I was a teenager, my family's house was broken into when we were all in the house! My mom's bedroom was on the main floor, and she though it was just me raiding the fridge. Then she wondered why I was using a flashlight.
Anyway, it happened twice. Different houses. Different neighbourhoods.
I've had alarm systems ever since. I'd recommend them -- not just for burglars, freaks and crazies (statistically it's getting less likely). There are other advantages. Central monitoring systems can now receive warnings about smoke, heat and flood (among other things). If they can't reach you immediately, they'll call the appropriate service, like the fire department. In the case of flood, I've got a flood sensor in my fish maintenance room, where the sump and most of the risky stuff for flooding is located. If a flood alert goes off, they'll call me or one of my reef buddies, who has access to the house if I'm gone.
I know this sounds expensive, but it's worth it for me. Some alarm companies will supply and install the bulk of the monitoring equipment for free on various contracts. One proviso, if you're thinking of this: check out LOCAL alarm companies; these are the ones that have local guards and local staff, rather than monitoring that's handled from god knows where.
I know this means nothing in the context of a smashed tank. But if theives have abused you once and they're not caught, they might come back once they think you've replaced everything through insurance. Who knows what these people think or how they behave, but get a good deadbolt at least.
How did they break in, btw?
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