Tide Clock

Template available as 416x240-BWRY for 3.7” ESLs and a simpler template, sized 250x128, also BWRY, for the cheapest 2.13” labels.

This mini tide clock is a 2.9” Gicisky device, less than £10 inc delivery in summer 2026.

Pre-requisites

A tides provider plugin for the Resources API installed and enabled, currently one of:

• signalk-tides - uses neaps library for international off-line coverage
• signalk-mareas-ihm - interfaces with official Spanish IHM tidal predictions, or falls back to Open Meteo and signalk-tides

For versions with the moon phases:

• signalk-derived-data - unlike other plugins, this publishes lunar and solar facts as SignalK paths

The moon phase is optional - without it, the moon icon is simply left blank and the rest of the tide clock still shows.

The tides templates can be customized to run with any tide provider, a specific one, or switch to other APIs or SignalK data paths.

• In the template it uses a SVG description like source=resources,resource=tides,provider=tides,path=extremes[0].time,format=local_time to get the first tide time, ensures it’s the preferred signalk-tides provider and makes it a simple local time rather than a UTC date-time.

To show the lunar phase, the environment.moon.phaseName path is required, which can be easily achieved by installing and configuring the derived-data plugin.

Tip

If testing this without a boat, you’ll need another plugin to provide navigation.position and navigation.datetime to make the moon and tide calcuations work. signalk-datetime can be configured for the datetime, and signalk-sailboat-simulator for the postion; other ways may work too.

Template Reference

The tides template family picks the best size for each label automatically - see Template Families.

Template: tides

File	Size (px)	Aspect ratio	Colours	Fits these labels exactly
tides/416x240-BWRY.svg	416 × 240	1.73 : 1	black, white, red, yellow	Zhsunyco 3.7” BWRY
tides/296x128-BWRY.svg	296 × 128	2.31 : 1	black, white, red, yellow	Zhsunyco 2.9” BWRY, Gicisky 2.9” BW, Gicisky 2.9” BWR, Gicisky 2.9” BWRY
tides/250x128-BWRY.svg	250 × 128	1.95 : 1	black, white, red, yellow	Zhsunyco 2.13” BWRY, Gicisky 2.1” BWR

Data used

Source	Path	Options	Used in
tides resource (provider tides)	extremes[n].label	-	all
tides resource (provider tides)	extremes[n].level	category depth	all
tides resource (provider tides)	extremes[n].time	format local_time, format day_mon	all
tides resource (provider tides)	station.datums.HAT	category depth, round 1	416x240-BWRY
tides resource (provider tides)	station.datums.LAT	category depth, round 1	416x240-BWRY
tides resource (provider tides)	station.name	-	all
tides resource (provider tides)	station.source.name	-	416x240-BWRY, 296x128-BWRY
Plugin	local_zone	-	416x240-BWRY, 296x128-BWRY
Plugin	plugin_version	-	416x240-BWRY
Plugin	repainted	format local_datetime_short	all
Signal K path	environment.moon.phaseName	image from lunar_phases	416x240-BWRY

The original single-file version is also still available as tide.svg:

Template: tide.svg

File	Size (px)	Aspect ratio	Colours	Fits these labels exactly
tide.svg	416 × 240	1.73 : 1	-	Zhsunyco 3.7” BWRY

Data used

Source	Path	Options
tides resource (provider tides)	extremes[n].label	-
tides resource (provider tides)	extremes[n].level	category depth
tides resource (provider tides)	extremes[n].time	format local_time, format day_mon
tides resource (provider tides)	station.datums.HAT	category depth, round 1
tides resource (provider tides)	station.datums.LAT	category depth, round 1
tides resource (provider tides)	station.name	-
tides resource (provider tides)	station.source.name	-
Plugin	local_zone	-
Plugin	plugin_version	-
Plugin	repainted	format local_datetime_short
Signal K path	environment.moon.phaseName	image from lunar_phases