Fish Fix

Amends hardcoded sea level assumptions to fix aquatic mob spawning.

7.1K Downloads

neoforgegame-mechanicsmobsworldgen

Rent Server with this Mod

Screenshots

About this Mod

What is Fish Fix?

This is a mod for NeoForge 1.21.1. It addresses this bug in particular: https://bugs.mojang.com/browse/MC/issues/MC-226687. It simply fixes the consequences of the hardcoded "getSeaLevel" method by allowing the user to set their own sea level. This bug was fixed in 1.21.2.

This mod is primarily useful for datapack and modpack creators, or anyone who modifies world generation with the ocean in mind. By default, the mod uses the game's hardcoded values; they must be changed in the config for any practical effect.

I do plan on backporting this mod.

To be clear: this mod does not allow you to modify sea level. This must be done separately.

Contact Me

Dejeh on Discord

Please report any bugs on the issue tracker: https://github.com/Dejeh/Fish-Fix-1.21.1/issues

Available Versions

Fish Fix 1.0.0release

MC 1.21.1neoforge

July 12, 2025

How to Install Fish Fix on Your Server

Order Server

Order a Minecraft Java server with at least 4 GB RAM (6 GB recommended).

Set neoforge Loader

In the panel under "Egg", select the neoforge loader and matching Minecraft version (1.21.1).

Install Mod

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

Compatibility

Mod Loaders

neoforge

Minecraft Versions

1.21.1

Server-side

✓ Required

Recommended RAM

6 GB(min. 4 GB)

Frequently Asked Questions

Fish Fix server crashes on startup – what to do?

Most common cause: wrong neoforge version or insufficient RAM. Check the server log (latest.log) for "OutOfMemoryError" or "Mixin" errors. With Mado Hosting: ensure at least 4 GB RAM is allocated and the loader matches the mod version (1.21.1). You can switch loaders with one click in the panel.

Is Fish Fix compatible with neoforge?

Fish Fix officially supports neoforge for Minecraft 1.21.1. The Mado dashboard automatically detects incompatible loader combinations.

Server lagging with Fish Fix – how to optimize performance?

Recommended RAM: 6 GB (per 5 players). Use /spark profiler to check if Fish 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.