Swim Fix

A mod that fixes MC-220390 related to swimming

518 Downloads

fabricneoforgegame-mechanicsoptimizationutility

Rent Server with this Mod

About this Mod

Swim Fix

An Architectury mod that fixes Minecraft bug MC-220390 for swimming in water.

About The Bug (From Minecraft Bug Tracker)

If you hit an entity while swimming underwater, the player will stop swimming for a brief moment (it changes the size of its hitbox and returns to the swimming one) and then get stuck in the middle of the water if they try to swim below a block (the player gets stuck when their large hitbox collides with a block, even if they are using a different size hitbox).

Supported Versions

Minecraft: 1.21.1+
Platforms: Fabric, NeoForge

Credits

License: LGPL-3.0

Available Versions

[NeoForge 1.21.1+] 1.1.0release

MC 1.21, 1.21.1, 1.21.2, 1.21.3, 1.21.4, 1.21.5, 1.21.6, 1.21.7, 1.21.8, 1.21.9, 1.21.10neoforge

November 20, 2025

[Fabric 1.21.1+] 1.1.0release

MC 1.21, 1.21.1, 1.21.2, 1.21.3, 1.21.4, 1.21.5, 1.21.6, 1.21.7, 1.21.8, 1.21.9, 1.21.10fabric

November 20, 2025

How to Install Swim Fix on Your Server

Order Server

Order a Minecraft Java server with at least 3 GB RAM (4 GB recommended).

Set fabric Loader

In the panel under "Egg", select the fabric loader and matching Minecraft version (1.21.10).

Install Mod

Open the mod browser in the dashboard and search for "Swim Fix". Click "Install" – done! Alternatively, upload the .jar via SFTP to the /mods folder.

Compatibility

Mod Loaders

fabricneoforge

Minecraft Versions

1.21.10, 1.21.9, 1.21.8 (+8 more)

Server-side

✓ Required

Recommended RAM

4 GB(min. 3 GB)

Frequently Asked Questions

Swim Fix server crashes on startup – what to do?

Most common cause: wrong fabric version or insufficient RAM. Check the server log (latest.log) for "OutOfMemoryError" or "Mixin" errors. With Mado Hosting: ensure at least 3 GB RAM is allocated and the loader matches the mod version (1.21.10). You can switch loaders with one click in the panel.

Is Swim Fix compatible with fabric and neoforge?

Swim Fix officially supports fabric, neoforge for Minecraft 1.21.10, 1.21.9, 1.21.8. The Mado dashboard automatically detects incompatible loader combinations.

Server lagging with Swim Fix – how to optimize performance?

Recommended RAM: 4 GB (per 8 players). Use /spark profiler to check if Swim Fix consumes the most tick time. Common fixes: reduce server view-distance to 8-10, install "performant" or "starlight" as supplementary mods on Forge. With Mado Hosting, your server runs on NVMe SSDs with dedicated CPU cores for minimal latency.