Flexible bag tanks have been known to fail at the fittings due to excessive movement of the tank. When half full the contents will move violently in a heavy sea as there are no baffles.

Flexible tanks can be awkward to install …they should have slats between the tank and hull so as the hull can breath and also avoid chafing of the bag on the hull.Flexible tanks when used for waste have a reputation of smelling badly. With no vent the contents turn sceptic. Thick walled polyethylene tanks are completely odour free when used for waste.

Flexible tank that has failed at the fitting.