Dwarf aquarium lily help/questions

[crazyshots]

I have a few questions about my dwarf aquarium lily, In the first image you can see tiny holes in the leaves which I'm pretty sure is a potassium thing but my bigger concern is the what looks like chunks taken out of the leaf(s). I used to use three root tabs a month but as it's grown I use six a month maybe I'm still not using enough or I need to use a liquid fertilizer as well. I'm not sure what the cause of this is whether it's something with my water, Not enough fertz or if it could be my amano shrimp beating the crap out of it. I have had water sprite in this tank before that they quite literally shredded they would pluck the leaves off of it and cause damage to the stems that eventually killed off the water sprite. I also have god knows how many snails in here and I'm not sure what kind they are. I have six Amanos and too many snails to count in a 10 gallon tank, thanks for any advice/help you can provide.

[Zenzo]

I have had a similar issue with this plant when a tank is overrun with snails. I would start by addressing the snail population while continuing to care for the plant. I highly doubt it is the shrimp. My bet would be on the snails. 

[crazyshots]

Thank you for the help, My last guess was the snails for some reason but I'll get on that maybe it's the perfect excuse to get some pea puffers that I've been hesitant on owning for awhile now.