Using this tide table: https://tidesandcurrents.noaa.gov/no...hi&action=data
I checked the NOAA tide tables against the G-7900 tide graph from 21 SEP 17 to 22 OCT 17 and it was within approximately 90 minutes of the highest tide forecast for any given day. On most dates it was well within 60 minutes. I've heard that Casio tide graphs don't work for California but this doesn't seem too far off for non-critical things like spontaneous fishing. Am I wrong?
I also compared a few lower high tides on the tide table to the tide graph and there was a greater difference, a difference of up to 3 hours.