We all mention things like battery's, motors ballast.
But don't seem to mention anything about adding foam or other forms of flotation.
In a model Submarine this is important, but not so much in a model boat.
For the benefit of new guys to the hobby it is put in to a model boat just incase you suddenly end up with a lot of water getting into your boat.
Hopefully you can get enough flotation in it so that it dose not actually sink and you will be able to retrieve it.
Do any members have some hints or methods on this subject that will help other members and new guys.