Retro style vintage cast iron pipework parts that I use to put together in my Victorian / Steampunk / Shipwreck inspired Aquarium designs.
Video below extracted from Practical fishkeeping article published on my colum tank after maturing for two years.
Printed in ABS, and resized in Cura to the sizes I need at the time (standard 50mm inner)
I then sand or texture with "no more nails" then paint and finally coat in resin to seal the paint.
Example build ...