Okay, this stuff can be a lifesaver for your java ferns, anubias, etc, especially if you've got tons of 'em. Thing is ... you're gonna need patience ... and I know how hard that is for folks that want that instant fix. Plants just don't work that way!
This Potassium will feed the plants what they need to make their fresh, beautiful leaves. It WON'T do squat for the leaves that are already full of holes; you're gonna have to do the maintenance and clip those off yourself.
I have a 240 gal. that has been going a few years, chockablock full of plants. They've all been getting the fertilizers Aquarium Co-op has ... and doing great, until ~4 months ago, when I noticed a lot of holes, especially in the Java Fern. I was observing a bunch of tiny rabbit snails munching around the holes, and assumed they must be doing the damage ... except they never used to. After seeing how the Easy Potassium gives the ferns what they need to stay whole, I notice the rabbit snails are still there ... just not bothering the intact leaves. Apparently they'd been attracted to the damaged spots on the leaves, and just doing their job. The Potassium has fixed the issue.
NOW .... sure, there are plenty of other companies marketing this sort of thing, and I'm sure they're plenty effective as well. What makes the Easy line of fertilizers ...well, easy ..... is the simple pump applicator. 1 pump, ten gallons (of water!). Simple. I use the full line twice weekly in all my tanks, and the plants are all doing great. Heartily Recommended by this guy that's been an aquarist for over a half-century!