Hey mocha the amswer is 1100am or 930pm depending on what day it is....
I know its not the answer you want but as it changes through the year and moon location it varies..
Unfortunately you have to use the calculator..
There are a couple good online ones...
If however you are programming a tide watch whilst the watches are accurate to some degree they do not always calculate the slack tide i think it is your looking for, also dependent on locallity this slack tide in perth as compared to margies may be 15 minutes different or up to an hour or two...
I use a lot of the fishing web pages for the tide info as they seem to take tides a bit more serious than us surfers.
I know you are probably smashing your keyboard in frustration at the moment and I too have been there, I feel your pain and often thought of forming a think tank or group called the lunar (tic) tidal group.
The question you ask is like when on hitchikers guide to the galaxy they ask the supercomputer for the meaning of life....
41 or 42 it responds..........

What do you mean 41 ????

Anyway google can only help you from here siri has an attitude problem