scales on raft bottom

[Lawdog]

I pulled my Avon raft out after a full season, and found white scaling on the bottom, or some type of shell attached to the bottom. Any hints on taking it off?
Thanks
Neal Weinstein
Enterprise E38

 

[chaco]

Blast Em!

First I blast them critters with a hose nozzle. Then I clean them off with a brush. Then I use a giant green synthetic cleaning pad with ZEP Orange
liquid cleaner. This is a great project for kids. Its kind of like Science Class
to GUESS what all the alien life forms are. No more wondering about the
origin of life !

Dan Simpson
E35-11
Merlin
Oceanside, CA