As the title says, the Hydrofluoric Acid quest isn't possible to complete due to the Mekanism fluorite being replaced by the Gregcraft one. The Gregcraft fluorite does work for recipes, but in order to complete the quest it requires Mekanism's fluorite. Just requires a change for that quest to require the Gregcraft one instead of Mekanism's "disabled" gem.

Edit: The quest does complete if given the item through commands, but I could not find a non-cheat way to complete the quest.
Edit 2: ATM 9 version is 0.0.23. Not sure if the issue persists through newer versions, as I haven't updated my server to 0.0.25 yet.

Noticed previous issue was opened about it, so closed this one.