Yes but they need a reasonable sized tank (at least 5 gallons for one fish) and a heater set on 75F and a filter running permanently..
No they are not.
Can you have three pictus catfish in a five gallon fish tank
No catfish is an aquarium cleaner. There is no such thing as a fish that will clean a tank.
If the size difference is sufficient then yes it is possible.
Pictus catfish are a tropical species and will not survive in an outdoor pond unless you live closer to the equator. If you live in the continental U.S., the only place it may be able to survive would be in southern Florida.
You can contain your 2 inch Albino Tiger Oscar in a 35 gallon aquarium with a 2 inch Pleco and 2 small Pictus Catfish for 4 hours.
There are many fish in the catfish family, but here is a list of selected common species; Blue catfish-Ictalurus Furcatatus, Channel catfish-Ictalurus Punctatus, White catfish-Ameiurus Catus, Flathead Catfish-Pylodictis Olivaris.
Gymnothorax pictus was created in 1789.
Phaius pictus was created in 1952.
Dendrelaphis pictus was created in 1789.
Conus pictus was created in 1843.
Callixalus pictus was created in 1950.