Alentia---
I did try an experiment with the hood air going down into water, and bubbler holes in the end of the submerged pipe. The problem is that before starting the air flow, the water level inside the hood outlet pipe is the same as the water level in the bucket, and enough vacuum must be created to pull the water level inside the pipe down to where the bubble holes are. This creates a heavy load on the blower, and drags down the overall air flow considerably. This load is less, if the bubble holes are at a shallower level in the water.
Another experiment I tried was to merely point the hood outlet pipe directly at the water, but a half inch or so above it, eliminating the need for bubbler holes. The force of the air flow appeared to blow all the air against the surface of the water, thus forcing all the fumes into the water. A pH test after running a couple of AR evaporations indicated that most of the acid fumes were trapped in the water. I also had NaOH in the water.
I haven't had time to set up my next version, which will be directly through a shop vac, with a teflon painted impeller. This one has two filters, a typical cylindrical one, plus an optional "dust bag" insert. I will probably put a furnace filter in the fume hood, too. I'm looking for the optimum performance, at a beginner home refiners' budget. I'm finishing up some other projects, and will be able to do this one next, and will post some results and pictures when I do.
Samual's drawing looks like the basic standard configuration for anything larger.
There are a few other fume hood threads on here too, if you use the Search feature.