Water Light Level
by HasselAssel
Players who build underwater can use Water Light Level to see which water blocks fall below a chosen light threshold, shown as a translucent aura around them.
What it does
On the client, Water Light Level draws a see-through aura over every water block whose light level falls under a threshold chosen by the player. The mod is released under the MIT License and is open source.
The scan covers a configurable distance around the player, and a larger range takes more time to render, so very large distances can cause lag because the area is scanned continuously. The aura color is set as an ARGB value written in HEX, which controls its transparency as well as its tint. The aura can be turned off or on instantly, or toggled with a keystroke.
The mod targets only Minecraft 1.21.11 on Fabric. Because it runs on the client alone, servers and other players do not need to install it, and it changes nothing about the world itself.
Key features
Low-light water highlighting
Water blocks below the chosen light level are outlined with a translucent aura, which helps spot dark underwater regions.
Adjustable light threshold
The maximum light level for highlighted water can be set, so the aura marks only the blocks that matter for a given check.
Configurable scan distance
The area scanned around the player can be widened or narrowed, trading coverage for rendering cost.
Custom aura color
The aura color and transparency are set as an ARGB value in HEX, so the highlight can match a build's palette.
Instant toggle
The aura can be switched off or on at once, or bound to a keystroke for quick checks.
Gallery
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Who it’s for: The mod suits players who build underwater, map makers checking mob spawning areas, and anyone debugging the lighting of a water feature.
How it compares
Visual Keystrokes is a client-side Fabric mod for 1.21 – 1.21.11 under All rights reserved, and it shows key presses on screen rather than light levels. Redstone Underwater is a Fabric mod for 1.21.11 that runs on client and server, is open source under the Mozilla Public License 2.0, and works on the server as well as the client. Water Light Level differs from both by covering a single visual task on the client side only.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Water Light Level | Fabric | 1.21.11 | Client-side only | 2026-03-16 |
| Visual Keystrokes | Fabric | 1.21 – 1.21.11 | Client-side only | 2026-02-15 |
| Redstone Underwater | Fabric | 1.21.11 | Client and server | 2026-02-09 |
Questions
Does Water Light Level need Fabric API?
Does a server need Water Light Level installed?
Which game version does Water Light Level support?
In the catalog
Water Light Level is one of 8,499 Technology mods on ModsFinder, and one of 4,201 Technology mods for Fabric. 19,862 mods support Minecraft 1.21.11.
Similar mods
What the author says
🌊Water Light Level is a client-side Fabric mod that visualizes underwater blocks whose light level is below a configurable threshold. It renders a translucent aura around qualifying water blocks, making it easy to: - spot drowned-safe areas - identify dark underwater regions - explore and debug underwater lighting
Official listing
- Modrinth page
- modrinth.com/mod/water-light-level
- Owner
- HasselAssel
- Published
- 2026-01-28
- Updated on Modrinth
- 2026-03-16
- Facts verified
- 2026-10-15