Are my fish eating my plants?

[CamERER]

is it a deficiency or are my fish eating the plants? Just got them 2 days ago and there already getting holes.
Stock:
6 gold barbs
2 sword tails
1 Nerite snails

 

[Fresh2o]

The barbs might be suspect. Those looks like crypts; older leaves have a tendency to dissolve/melt off rather quickly.

 

[Autumnsky]

What are the foods you feed the fish?

 

[Angellove78]

Looks like melt.

 

[CamERER]

I feed them big bites but I think it is melt thanks for all the help!