The KAB traps all the fluid. As such, it can be used with a wet or dry vac and I use it with a Filter Queen dry vac. KAB does not recommend its use with very high powered shop vacs; your central vac would be fine with it.
As to fluid usage, it will probably depend on what system and brushes you are using and perhaps what fluid you are using. I have a scrap turntable (arm ripped off, motor still functioning) beside my KAB for applying the fluid. I use the RRL fluids. Using carbon fibre brushes, you need to get enough fluid on the record simply to have the fluid pooling in front of the brush. Not very much and having the fluid puddling all over the record will not get you a cleaner record than using a minimal amount. I use a pipette/eye dropper to apply the fluid to the record before brushing, about 7-8 decent sized drops from inner to outer edge. $70 Cnd. worth of RRL (Super Deep and SVW) will clean approximately 250-300 records using this method.
As to fluid usage, it will probably depend on what system and brushes you are using and perhaps what fluid you are using. I have a scrap turntable (arm ripped off, motor still functioning) beside my KAB for applying the fluid. I use the RRL fluids. Using carbon fibre brushes, you need to get enough fluid on the record simply to have the fluid pooling in front of the brush. Not very much and having the fluid puddling all over the record will not get you a cleaner record than using a minimal amount. I use a pipette/eye dropper to apply the fluid to the record before brushing, about 7-8 decent sized drops from inner to outer edge. $70 Cnd. worth of RRL (Super Deep and SVW) will clean approximately 250-300 records using this method.