Orchid bark will easily raise the humidity well above 50% if you make it damp. Royals are an African python - are you sure that 50% is what they require? my limited experience of africa (which is limited to the north and north east, admittedly) is that it is very dry...I'd go with aspen, newspaper or similar.

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1.0.0 Honduran Milksnake CB06 (Marley)
1.1.0 Crawl Cay BCI CB07 (Clarence&Alabama)
0.0.1 75%JJ Carpet Python CB08 (un-named)

i beleive they are from west and maybe south africa
50% is perfect ,i think

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0.1.1 Corns (Venus and Popcorn)
1.0 W.hognose (Hector)
0.1 Cali King (Cleopatra)
4.8 Royal Pythons (Ullyses,Prometheus,Rameses,Xerxes,Trinity,Ripley, Aphrodite,Phoenix,Tallulah,Delilah, Storm and Andromeda)

yup 50% is spot on and if you wet the orchid it will defo go much higher than 50% humidity

aspen or hemp bedding as you can just put in a moist hide and that will prob make the humidity right

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SNAKES:0.0.1 06 Dwarf great plains rat snake1.0.0 05 snow motley1.0.0 07 strawberry snow0.1.0 07 snow1.0.0 07 normal1.0.0 04 anery x rat0.1.0 04 hypo x rat1.0.0 06 bloodred het pewter (serpenco)1.1.0 07 butters0.1.0 07 anery0.1.0 07 motley0.1.0 07 creamsicle 1.0.0 06 miami0.1.0 03 anery1.1.0 07 amels
08 HATCHLINGS:0.0.8 anery0.0.4 rootbeer0.0.1 creamsicle0.0.1 snow

MY NAME IS JAMIE AND IM AN ADDICT

Not to mention that with orchid bark the "Soil/dust/whatever" that comes off the bark can clog the Royal's labial pits.

Orchid bark has its place with tropical species, but there are better substrates for Royals.