I'll be darned... It's been so long since I've seen corrugated hose with cuffs in a sanitation system that I completely missed it in his photo
till I took another look after reading your post...Good catch!
Nobody paid much attention to sanitation hoses till holding tanks
came along. Corrugated hose had a brief run in the 70s and 80s, till people figured out that the corrugations trapped waste and sea water minerals, plus it permeates pretty quickly and first hoses actually rated for sanitation--smooth interior
walls with a helix that prevented the hose from collapsing--came along... #148 flex pvc, which is still on the market from several mfrs 'cuz it meets that standard and has the lowest price
. Unfortunately it often permeates very quickly too. Higher quality, more permeation resistant-- and therefore higher priced--hoses began showing up in the mid-90s and continued to evolve until now there are several that have proven to be just about 100% permeation resistant. It's the last place you want to save money
by going with cheap
hose if you only want to go through the misery of replacing hoses just once.
Btw...Happy New Year, y'all!