Wow. Ppl really are getting dumber and dumber. BUT on the other hand the ones pressing the charges don't seam to be that smart ether. To the best of my knowlege you can't be charged with animal abuse for a fish. Distruction of personal property maybe but not animal abuse.
As far as I know you can be charged for animal cruelty if you kill off someone elses fish stock. People have gotten animal cruelty charges for dumping bleach into tanks which resulted in the death of the fish before (one article of which was posted on here a long time ago).
Here's a link to animal cruelty laws. Some specify the types of animals covered. Some say companion animals(which to the best of my knowledge fish aren't) and some say any animal. So it could be possible to get charged with it. But any half decent lawyer could easily get you out of it. Simply present several feeding videos from YouTube to the court, and argue that the owners knowingly placed a animal in a hazardous position, why aren't they being charged as well?? I just don't think most people will see fish as a sentient being, and thus should be covered by those laws.
PS. Not defending their actions at all. And really hope they get in a lot of trouble, but I'm totally against prosecutors tagging on as many little things as they can think of. Especially things that can fall apart so easily in court......really I just have dumb ppl.