My fish has started eating my Brazilian sword... is that bad? He never ate it before today...

fish are a lot more intellgent than most people think ,the 3 second memory thing is complete rubbish and has been proved by many scientific research! I would say that ure fish may have sampled a leaf by accident and discovered a gr8 tasteing plant and thus begun eating it!
also are there n e other fish spices in your tank?
and have u got snails in your tank? ( you may not think u have but i acc`dently introduced my snail (boris johnson) into my tank on a new plant) thankfully he doesnt cause much damage to my plants!!

i have 1 black moor and i used to have snails before he ate them all! I saw him eat his first one... I think he was more shocked then I was! LOL! The thing is- I have that a-something or other plant and he practically destroyed it (as expected) but hasn't eaten much of it in the last day or 2... He's made the other plant his victem! I'm just worried b/c the pet shop said it was more decrative than edible...

Its not unusual for goldies to eat plants that are supposed to have a low edibility appeal for goldfish. They just seem to develop a taste for some of the more (previously) unappetizing plants sometimes. <_<