Your Post brought back a few memories Paul!

I kept Tropical & Marine fish many moons ago, and swmbo saw this (to her!) beautiful Butterfly fish in the tropical section of our local pet shop, so I bought it. Everything was ok for 24 hours until I began finding half a Guppy here, & a third of a Red Tailed Shark there! So I determined to find the culprit and kept a beady eye on the tank, admiring the Butterfly fish as it cruised quietly just under the surface minding it's own business

THEN..... a Zebra Striped Dannio cruised lazily past the aforementioned bag of shi* which promptly opened this mahoosive jaw like a cross channel ferry and flashed a set of fearsome gnashers that wouldn't have looked out of place on a bleeding Dinosaur & demolished said Dannio in one snap!

I'm ashamed to say I netted it 'At the Double' & despatched the bugger down the WC pan!
You won't have that problem with your variety, but you will have to be on the lookout for certain types of birds, notably Herons & the like, which love a bit of fresh fish & can see them from a fair height, so keep an eye out!
