Where can I find colored O-rings for kayfun/orchid tanks?

[relink2013]

I am starting to see more and more pictures of people with kayfuns and orchids with colored orings with clear tanks. I have plenty of clear tanks, but I cant find any color oring except black, and the red ones that come on fasttech stuff. Can anyone tell me where I can find colored o-rings that will fit on the kayfun/orchid tanks? specifically blue.

 

[Lova]

I'm not sure of the dimensions for Kayfun or Orchid o-rings, but I guess you could test out o-rings from here: https://www.crazy-factory.com/product_listing_ng.php?q=o-ring#

Yeah I know they are piercing o-rings, but they are silicone so I would imagine they would work with tanks, just get them in some diameter and test them out.