Hippo Rocks is 800m downstream of Tombi and is essentially a short, steep drop into a large flat pool. The main current flows over, under and around some big boulders making for an extremely hazardous line. It is therefore recommended to take the sneak on the right. You can attempt to go down the main channel in very low river levels if you know exactly where you are going, but be warned it is still a challenging option. Hippo can be portaged on the right over the rocks in low water and in high water the left is a better option.
In medium river levels there is a sneak around the right of the little island. It takes you down an exciting shoot that meets up with the main channel after the danger area. If the water is high enough there is an even easier line over the "high side" on the extreme right into the big pool. Drop over slowly facing left back into the main channel.
How do you know when you are approaching Hippo? Look out for the distinct large boulders as the valley opens up.
For the sneak go right of the first boulder. For the normal line keep left. For the "high side", if there is enough water, keep centre-right. The images below were taken on at a medium-low level. At higher levels the same line applies however the channel is much wider.