SOLVED. YA Fantasy series. Boy travels to magic world, has to visit groups of elementals (earth, water, fire, air) to convince them to fight against evil. Water element named Tide. Read in 2010-2013. Spoiler ahead. [s]

[Lily]

In the magic world MC befriends a girl who has been bullied for having no magic.
Each book centers around MC visiting another group of the 4 elementals: earth, water, fire, air. The book covers are of the group of elementals he is visiting. There are 4-5 books in the series.
There is a water elemental named Tide who betrays the elementals, sides with evil.
I'm pretty sure at one point MC's friend ends up in the nonmagic world, tries a milkshake for the first time.

[Kris]

Lily, I added some details and a spoiler alert to the header/topic title. You can update it by clicking the small "edit" link after the header. This only works on the full Desktop website - not the Mobile website or app. (On the Mobile website, click the "Desktop version" link at the bottom of the page.)

[Marisa]

Google brought up Water Keep. Is that your book?

[Lily]

Yes it is, thank you!

[Lily]

Thank you, I should've thought to add a spoiler warning. I found my book!