Pseudoscorpions

Housing:

Something like a half gallon jar or similarly sized enclosure with an airtight lid is recommended for starter cultures, to make it easier to view colony health.

In general it seems moderate to high ventilation is preferred by the majority of cultured species, micromesh ventilation or something similar is suggested, as these are tiny arachnids, and all life stages of most species seem perfectly able to scale smooth surfaces.

An inch or so of substrate such as coco fiber, potting soil, sphagnum peat, etc., topped with at a few inches of coco coir chunks, mulch, or bark pieces works well for a majority of cultured species, though exact substrate/hide preferences will vary species to species.

A humidity gradient, erring on the drier side is preferred by most cultured species; excessive humidity and condensation will rapidly kill many Pseudoscorpion species. I keep most species on a 40/60 horizontal humidity gradient, erring on the dry side. Complete dryness can also kill cultures quickly, so maintaining a proper gradient is important to keeping these tiny arachnids happy.

Diet:

Preferred diet varies from species to species, most in culture will readily accept a variety of springtail species, but some prefer mites (like Oribatid mites), others micro-roaches (like Compsodes or Nocticola). Some may even be Psocid specialists, so testing different food sources and figuring out yourself which works best for the species you are keeping is a good idea.

If not consistently topped off on food, many species will quickly resort to cannibalism, especially of their own offspring, so a consistent and ample supply of food is very important.

Temperature:

Most species I've kept breed readily at 75-85F°, and I'm sure many will breed at room temps. Some may require diapauses for consistent breeding, though I've yet to come across any such species in my own breeding.

Breeding/Life Cycle:

Females generally carry their eggs underneath them until they hatch, sometimes they are mobile during brooding, other times they construct silken chambers for this. Brooding usually takes around 1 month. Development times vary a lot between species, most seem to be in the range of 6-8 months or so from hatchling to adulthood, if fed amply at least. Most species construct silken chambers to molt inside of, said chambers are often covered in substrate as camouflage. All life stages can be kept and reared together, as long as you stay on top of feedings, and they have lots of surface area to get away from each other if needed.

The urge to use these as a sort of cleaner crew or pest control in other invertebrate enclosures is understandable, however most species will not make a dent in most serious pest invert populations, but can decimate the springtail population in an enclosure. Because of how picky some species are about their humidity preferences, they may just die out rapidly in an enclosure not tailor made for them, or escape if the lid isn't airtight or ventilation holes are too large. Overall while some species may get along in certain bioactive setups in certain situations, if your end goal is to maintain a healthy population of Pseudoscorpions, keep them going in their own enclosure first.

Species notes:

Chelifer cancroides:

A slender, cosmopolitan species, also quite territorial it seems. These guys need to be smothered in food (preferably springtails) in order to coexist and breed in any numbers, and also appreciate lots of surface area. Excessive humidity is a death sentence to these and many Cheliferids.

Cheliferidae sp. "Ector County, TX":

This is a good beginner's Cheliferid IMO. Breeds readily so long as ample springtails and surface area are provided. Will also feed on Psocids if available. Females have pretty large clutches, and thankfully this species doesn't seem too territorial.

Cheliferidae sp. "Flamingo, FL":

A small species, slow breeding and seems to possibly be more on the more territorial side. As is typical for this subfamily, springtails seem to be the preferred food source.

Cheliferidae sp. "Wellston, OH":

Likely a Chelifer species, this is probably the largest Cheliferid I've worked with yet. Likes ample space but doesn't seem super territorial, again though they need to be topped off on food at all times to grow in decent numbers (springtails are preferred).

Chernetidae sp. "Livonia, MI":

This small species spends most of it's time underground, so less focus on a chunky top layer on top of the substrate, and more focus on a deeper, chunky substrate itself is recommended. They will eat springtails but also seem to enjoy mites in their diet, Oribatid mites seem to work well. Slow breeders, and not very prolific. 

Dinocheirus arizonensis:

A very impressive species, the largest in US culture, maxing out around 6mms (not including pedipalp length) and chunky. These have pretty standard care, and prefer a mix of springtails and micro-roaches in their diet (offering springtails alone can seemingly lead to some cannibalism amongst adults). Younger instars tend to burrow just below the surface of the substrate, whereas larger juviniles and adults spend more time above ground.

Paratemnoides nidificator:

This species is unique in being very communal, they construct silken chambers in between flat bark pieces (their hide of choice), in which all life stages will huddle together and even molt within. I haven't witnessed any significant cannibalism in this species myself, even between different life stages. They will not feed well on springtails, micro-roaches are the best food source. They can take down surprisingly large prey compared to their size, and will feed communally as well. Slow breeders, but they make up for it in their unique lifestyle and relatively large size.