larvae in tank (part 2)


OK, here is some followup to my questions:

I have found that many of my broad-leaves plants including a few Anubias (I 
think - it fit the description) have holes on quite a number of leaves. I also 
found a small snail (could be a pond snail) in my tank. Unfortunately I dropped 
it in-between leaves while trying to remove it from my tank. Will look for it 
again. So, which one is the main culprit for destroying my plants? The snail or 
worm? I've seen the worms have homes out of fresh plant cutting but have yet to 
see the snail eating my plants yet.How can I terminate all these uninvited 
guest. Thanks.