slack tide vs tidal swing

[Jimmyz123]

If I understand it correctly the slack tide you are talking about is the peak or the bottom of the tide swing in question. As Yani mentioned study the charts and it should tell you what type of lenght you are looking at. some tide peaks or bottoms may be longer than others.

Here's a link that will help you understand tide chart reading
http://www.coos-bay.net/understanding-tides.html