Hey guys and gals

Noticed today that there is a small crack in the long range tank on my 2011 patrol. The crack is on the front side of the tank and is about 10mm long going horizontaly. Would like to get it sorted pretty soon as it leaks when I fill the tank up past a certain point.
Just wondering how it can be fixed and if I would be able to do it myself or would have to take it to somebody.

Thanks in advance