Perhaps you are confusing the water for slime and the slime for acid, which quake 1 did not have. There was nothing called acid, what it was always called (as stated BY THE VERY subject document here) was slime. Quake 1 had 2 instantly damaging fluids/textures slime and lava. That is literally what they are in the source.
What a weird discussion, disputing a document that was written 25 years ago contemporaneous with the subject. There’s no misremembering here and this document trumps yours or anyone’s memory.
https://quake.fandom.com/wiki/Slime_(Q1) https://quake.fandom.com/wiki/Water_(Q1)
https://github.com/search?q=repo%3Aid-Software%2FQuake%20aci... https://github.com/search?q=repo%3Aid-Software%2FQuake%20sli...