[The Coffee]

So I suddenly started getting holes in my RTL leaves about 4 days ago. They have been and are still growing like crazy but the holes make me think that something might be wrong. Some holes appear overnight while others start out as green patches. (See pics)

Everything I read seems to point to holes being caused by Potassium deficiency. However, I always add potassium and both of my plants have several osmocote root tabs under them which I put in about a month ago. This makes me think Potassium deficiency is extremely unlikely since none of the other plants show symptoms and even if there wasn't enough in the water, they would be getting enough from the root tabs.

What else could be causing holes to appear suddenly?

Here are my specs:
55g fairly heavily planted with laterite substrate
DIY CO2 (giving around 25 ppm) +excel
Dosing Seachem Flourish, Equilibrium, Nitrogen, and Potassium
Fish are: Angelfish, Serpea Tetras, Black Tetras, Buenos Aires Tetras, young CAE's, 1 Krib, 1 Red-fin Shark, 2 Pearl Gouramis, 2 Kissing Gouramis

 

[JMN16150]

As far as I know.... tetras and gouramis love salad (I noticed them eat my aquatic onion to the bulb:/)

 

[The Coffee]

Well that does make sense. If it was a deficiency, I'm thinking the holes wouldn't have appeared suddenly. I'll see how it goes. As long its only small holes on some leaves I don't really care. Anyone else have any thoughts on this?

 

[Zapins]

I agree. Looks like fish damage. You can tell because the margins of the holes are sharp and there is no discoloration which you would see if it was a potassium deficiency. Holes also wouldn't show up over night and they would only be located on old leaves.