Its doesnt make sense at all.... why brake the tanks? A**holes! I mean they stole stuf and brake the tanks? that sound personal to me. When my mum got broken into when I was a kid they left her tank and dog alone just stole some jewelry and left again.
Some punk kids also broke into her garden once and messed up some plants, again the 1000 gallon koi pond was untouched.
sound like you have some one who holds a grudge and they stole stuff to make it look like a robbery and just wanted to break your tanks and make you mad.
sucks and i feel for you! TEAR THEM A NEW ONE FOR ME!!