In a message dated 5/4/98 7:44:58 PM, you wrote: >Right now I am using the modern silicone sealant, >but would like to be more authentic in my restorations of old aquariums Why would anyone want to return to yesteryear and use that black stuff. I worked with for years and it never was any good. It will leak and will deterioriate and never do 1/10 the job that silicones will do. Lee Harper