my silver aro became blind because both of its eyes got eaten by his tankmate a giant red tail gourami. it died of starving because cant hunt for food. i was 12 at the time so yeah dont let ur children take care of their pet on their own lol!
my worst experience with arowanas is, about 11 years ago, my mom wanted to paint the wall behind my tank of a 4yr old aro. only way to do so is drain the tank and move it. i said no paint around it, she dissagree'd with me.
when i was gone, she drained it, and moved it over to paint behind it, when she moved it back and refilled the tank the aro died from shock and all the crap he went thru. the tank was drained like 80%