mysterious disappearance

[Marnix Hoekstra]

My female grandis Isabela has a tank of her own. Until last week there were two big goldfish in her tank, always chasing each other. They had been there for a year.
When I came home last week one goldfish was floating dead in the water, without any injuries. And the other goldfish had disappeared. I've emptied and cleaned the whole tank, but I found no trace of it.
Isabela is the only suspect. However: in 17 years she has never eaten fish, let alone a living fish.
The only scenario I can think of is this:
One goldfish died. The other goldfish, having lost its friend, started chasing Isabela. Isabela got annoyed. She killed the goldfish, and ate it.
I wish I had seen it!
I don't feel bad about losing the goldfish. They were originally intended as feeder fish (for a RES that didn't eat them). I'm just wondering what happened.
And Isabela looks innocent like always.

[Philip]

That's an interesting story, indeed.
You'd wish you could ask the turtle what happened, aye?