Piece of Heart #30
Drop down from the previous Piece of Heart and you’ll spot a small pond of water. Collect all the Fish here in Bottles then go to the Marine Research Lab . There is a tank to the right as you enter, climb up and dump all of the fish inside.
Once one of these fish eats four other fish, it will devour the other fish in the tank and spit out a Piece of Heart. If you aren’t lucky enough for one fish to eat all four that you just collected, you’ll need to go back and get more.
Piece of Heart #31
Exit Zora Hall and swim to shore. Follow the land around to a waterfall with a small pool at its base. Use the Zora Mask and dive to the bottom where you’ll find some Skullfish and a Like Like . Defeat them all to receive another Piece of Heart .
The Beaver Brothers
Exit the waterfall pond and use the Hookshot on the trees of the platforms along the canyon. You can collect some Red Rupees from the chests, but you want to reach the top so you can enter the Waterfall Rapids .
Here you’ll spot a beaver swimming in the lake, swim over and lock on to him and he’ll descend to the bottom of the lake. Put on the Zora Mask and dive then speak with him again.
Apparently, he thinks you want a Bottle (of course you do!) but he won’t just give it up.
He wants you to play a little game, follow him and complete his race in a certain time while swimming through rings. Agree to his terms to start the race, you’ll have 2:00 minutes and 20 rings to swim through.
The rings are solid so you can hit them and be thrown off track, be sure to swim through the center. The path itself isn’t too difficult and you can make up a lot of time by using Electric Barrier to swim faster during the straightaways.
Complete this segment to meet another beaver who will hand over the Bottle if you complete his race. This time you have 2:00 minutes and 25 rings , it’s the same course but with the 5 extra rings so you’re limited on using Electric Barrier for speed.
Complete this to receive Bottle #5 !
Piece of Heart #32
Visit the Beaver Brothers once more and challenge them again. You’ll have to complete each beavers race again, but you only get 1:50 to complete the circuit this time. Winning again will reward you with a Piece of Heart.