My amazon sword plant (beware... pics)

See that leaf that's kind of rotting away? I have a few like that on my sword plant.



Could this be the culprit? I also see my tiger barbs nipping sometimes at the plant...



He's always on one of those leaves (or hanging on top of the java moss)



Water is stable (ph 6.5ish, ammonia & nitrites 0, nitrates 10ish, kh 3 drops and gh 4 drops) lights on from 7am-7pm, once weekly ~20% water changes.

Thanks in advance!
~Tara

Thanks Len! Other than those few spots, the plant is grown so nicely, and even has 3 new 'buds' growing... what do I do with those buds? They are growing on the end of a really long stem...

~Tara

Thanks schiejr!! You can kind of see the long stem, off to the left of the sword plant in the picture. There are white roots growing, but they're still pretty short.

~Tara