Abstract: An internal baffle apparatus for use within tanks, in particular flexible tanks, for liquids for dampening surges of liquid, and tanks having such baffle apparatus, wherein the baffle apparatus comprising a plurality of panel members connected along a connection line that defines an axis wherein said panel members extend radially from the axis such that each panel member is oriented in a radial plane, and each panel member having a bottom edge, a top edge portion and a remote edge opposite the axis, wherein the bottom edge of each panel includes first connector means operable for connecting the bottom edge at a plurality of connection points to the bottom wall of the tank, and the top edge portion includes second connector means located remote from the axis that are operable to connect the top edge portion to an upper part of the tank.