Plant food v. fertilizer

[Confetto]

What is the difference between plant food and fertilizer?? 

I am currently using Aqueon aquarium plant food in my tank. I dose once a week (3 gal tank, just shy 5ml) and I'm guessing everything is good ???  After watching a few videos and reading posts here, many hobbyists seem to love Easy Green. So what's the difference? What am I looking for to gauge success? Do I have too many plants in my small tank that require more nutrients?

I mainly have beginner plants. I'm focusing on rhizomes and floaters. I have small river rock as my substrate.

I have struggled with frogbit, but half the issue is my betta loves to cuddle the roots and knock them off. I get new growth, however there's some mel ting from time to time. Currently, I don't mind buying a new handful of frogbit every so often, but I would love more success. I love the look of dangly roots and Miso seems to be a fan of them too. Perhaps a hearty pothos plant would achieve the look I'm going for.

I bought a small bucephalandra on a whim about a month ago & finally noticed new growth. 

Same with my hornwort/mystery plant. He was a hitchhiker with my last batch of frogbit and has already grown an inch, new roots and a new sprout. Clearly my fastest growing plant (or weed) in the tank. 

I completely understand that there is a balance and finesse growing aquatic plants. Full disclosure, I struggle with regular house plants, too. So many of you have posted pictures of gorgeous planted tanks, and I want to get there too. 

[Mmiller2001]

Fertilizer is fertilizer. Just name tricks.

[Mmiller2001]

I need to clarify. Don't go dumping terrestrial fertilizer in your tank. Example, no Miracle Grow and similar. If it's designed for aquariums, you are good to go.

[FLFishChik]

Fertilizer is just a fancy name for plant food! But they aren’t all created equally. As @Mmiller2001 said, use only fertilizers designated for aquariums in your aquarium. 
 

 Fertilizers all contain certain levels of nutrients that plants need to thrive and the right fertilizers depends on the type of plants you have.

[Confetto]

I was using Aqueon plant food in my tank and I don't believe it was doing anything. Just bought Easy Green feet and hoping to get better results.

I have two anubias, bucephalandra, Hornwort and frogbit in a 3 gal tank with a Betta. This is my first attempt at a planted tank and I know betas are poop producers. Hoping to discover the right balance of nutrients for my plants to grow.