There is more to Madu river than simply taking a boat tour and visiting attractions in the vicinity. You can do that while taking the boat ride. And remember to be cautious. You will find a lot of bridges across the river. You have to lower your head in such areas. You will be passing through the mangrove caves.
The mangroves are a sight to cherish. If you are lucky, you will be able to spot rare wildlife creatures in the mangroves. If you travel during the afternoon, remember to wear sunscreen. Best is if you can avoid afternoon, and take a ride either in the morning or afternoon.