There are a number of different types of media used in turbidity filters.
Which one used is dependent on the chemistry of YOUR water. That is why there are no manuals to tell you which one to use; water treatment dealers 'know' which ones work (best) in your area. That's due to the complexity of water chemistry from one well to another in one area or another. Not to mention the peak demand gpm variable from one house to another which dictates the size of the filter.
You have an off gas (vent) tank, as all oxidizing (chlorine, air, ozone, hydrogen peroxide etc.) filter systems should have and with air injection (uses a venturi as opposed to an air pump system) as you have, you don't want air added to the water stream before any type pressure tank, but it is done every day somewhere, out of ignorance; especially with a bladder type pressure tank.
A CSV will cause air injection while the pump runs until as Valveman says, the flow is too small for the venturi to add any. That will end up giving you too much air for your probably Honeywell/Baukmann (sic) float controlled vent valve (you have a smallish vent tank) and thereby too much DO (dissolved oxygen) in the water IMO and that can cause water quality and other problems and IMO you won't like that and there's nothing you can do but remove the CSV.
One or more of the types of media used in your type filter may require a higher than normal DO content but most don't.
On the other hand, dependent on the type of media in your filter, if you don't get enough air, the filter will not work for anything other than 'sediment' filtration (you don't use any air system for sediment removal). In other words it could not remove iron, H2S gas or manganese.
You need a water analysis on your raw (untreated) water (before any air is injected), then you can choose which media to use in the filter; or the only media that you can use IIRC, is birm. But birm can not be used if there is any H2S gas present.
You can clean your vent tank by removing the head and dumping/removing any sediment in the bottom etc.. Use two sch 40 PVC unions.