Every holding tank needs to have some manner of ventilation.
Waste holding tank vent.
No treatment chemicals needed automatic bypass valve reduces tank collapse.
From technical editor chris dougherty.
Unexpected sewage odors that appear in the bathroom area of your rv can indicate a clog in the air vent leading from the black water holding tank to the roof.
By design the patented 360 siphon can only create an updraft expelling odors and fostering an oxygen rich environment to speed up waste breakdown.
With no outlet for escape the noxious tank fumes seep.
Without a free exchange of air from the tank s air vent flushing the rv toilet creates a vacuum.
However sizing has to be taken into consideration.
So providing it is often the most effective and simplest approach.
Remember the aerobic bacteria which digest waste and don t produce odor in the process require oxygen.
The 360 siphon rv holding tank vent cap eliminates odors from the source the holding tanks and exhausts them out the roof vent before they have a chance to invade the rv living space.
The gray and black water holding tanks need ventilation to the roof but i see nothing in nfpa 1192 indicating that both tanks can t share a common vent.