Hello. I am 15 years old and i was just given a kayak. I am slowely turning it into a fishing kayak and wondering if i should invest in a fishfinder. This is the fishfinder that i am looking at. http://www.basspro.com/webapp/wcs/stores/servlet/Product_10151_-1_10001_58748____SearchResults#reviews

Also i am not sure how to install this. What kind of battery am i going to need?? Also i think there is something that sticks to the bottom of my boat if i get a fishfinder. is that going to get ripped off??