Error while running setup for entity prototype "space-elevator-fluid-tank" (storage-tank): Entity must be minable when next_upgrade is set. (was storage-tank2)
You can find the answer here
https://mods.factorio.com/mod/Kux-OrbitalIonCannon/discussion/64177276ca7690cb47d56f01

Thanks Naarkerotics! I can take a look. What version of the mod are you running? I haven't come across this just yet

Just had it in the latest update.
Its caused by other mods altering the base prototype for storage tank, which then leads to inheritance issues.
You can solve it on your end by recreating the storage tank for your purpose or just nixing the next upgrade.

Ohhh right, cause I'm deepcopying from base prototype. Should be fixed in 0.3.1 released just now, thanks for your report! :D