How do you get the second crystal in the legend of Zelda a link to the past?

go to the second templ! (water temple) go in to the ligt wold make water flow go back to the dark wold! get the hook shot! go thu the right waterfall and fight the boss! it is a eyeball boss hook the big eyeball's small eyeballs then hit the small eyeballs until they are all gone then the boss will roll and hop! when sucsessfuly doging the rolling he will hop equip with arows then the eyeball will be stungd shoot arows from the right angle until he dies! good bye and good luck!!!!!!!!!!