Live wallpapers and your MacBook's battery
An animated wallpaper is drawn by your Mac's graphics processor, frame after frame, and that takes energy. How much depends on how many frames it draws, how many pixels each frame has, and whether it keeps drawing when nobody can see it. Here's what Shoal does about each.
The rules Shoal follows
| When | What the aquarium does |
|---|---|
| Plugged in, desktop in view | Up to 60 frames a second |
| On battery | Up to 30 frames a second, without the light shafts |
| Windows cover most of the desktop (under 40 percent shows) | 20 frames a second |
| The desktop is almost fully covered (under 15 percent shows), including by a full-screen app | Stops |
| The screen is locked or asleep | Stops |
| Low Power Mode is on | Stops |
| You paused it, or Reduce Motion is on and Shoal follows it (the default) | Stops |
The fish menu's first line says what the water is doing: “Swimming”, or “Swimming on 1 of 2 displays” while it is still on the others. When it is still everywhere, the line says why, for example “Resting behind your windows” or “Still while Low Power Mode is on”. Hold Option while the menu is open to see the frame rate it's drawing at.
Settings that use less
- Low quality, free and made for older Macs, draws the least: it aims for 30 frames a second with a softer picture, simpler fish, stones and plants and no light shafts. Balanced, the other free setting, draws more. High quality (Shoal Pro) draws the most: sunbeams when plugged in, a moving web of light on the sand and stones, more detailed stone and leaves, and fuller planting by default.
- A 30-frames-a-second limit (Shoal Pro, Settings › General) keeps a plugged-in Mac at the battery rate, for quieter fans.
- Fewer fish and less planting (Shoal Pro, Settings › Scene): more fish mean more work for the graphics processor, and plant density goes from 30 to 100 percent.
- Pause for an hour, until tomorrow morning or until you resume, from the fish menu.
- Low Power Mode stops the aquarium entirely while it's on.
More displays and higher resolutions mean more pixels to draw. On very large displays Shoal caps the pixels it draws, so a 5K or 6K display doesn't cost as much as its full resolution would.
Seeing where your battery goes
To see how your Mac spends its energy, open Activity Monitor and choose the Energy tab.
When the aquarium isn't moving
A still aquarium is usually one of the rules above at work. When it is still on every display, the menu's first line names the rule; with several displays it says on how many the fish swim. The support page lists every message and what to do.