FTBQ Better Fluids (FBF) is an addon mod for the FTB Quests mod that adds a new Fluid+ task type.

This task type differs from the built-in Fluid type in several ways:

A Fluid+ task completes as soon as the player holds any item in their inventory or hotbar that implements the Forge fluid handler capability. This includes buckets as well as most modded tanks, cells, drums, etc.
A Fluid+ task can have its recipes looked up in the installed recipe viewer like item tasks can.
A Fluid+ task can have a list of fluids, any of which can complete the task, similar to using an "OR" filter from ItemFilters.

Recipe viewing is implemented in FTB-Quests 1.20.4, but it's not been backported to 1.20.1.

The Fluid+ task type is compatible with AE2 FTBquest Detector for single-fluid tasks.

why

Because the Fluid task type requires submission and has no recipe viewer integration (in 1.20.1), a lot of quest books that require the player to craft fluids fall back to using an Item tasks with a bucket of the desired fluid instead of using a Fluid task.

The Fluid+ task type fixes this by having a more flexible inventory detection mechanism and by allowing the player to look up that fluid in their recipe viewer directly from the quest book.