first of all, I think you are confusing ticks with rows.
a tick is a subcomponent of a row: a row is subdivided into a number of ticks which is set by the speed value, and is defaulted to 6.
that said, you can either raise the number of ticks into which the row is composed (using the command F1xx, where xx is the number of ticks, minimum 00, maximum 1F), or use the note delay command 0Dxx to delay a note by xx ticks (minimum 01, maximum speed-1)