[Public-List] Holding tank question

[John Riley]

We also have two vent lines led to the bow as shown on the maintenance 
page on the A30 site.  Works like a charm and no odors.

That's the thing...according to Peggy Hall ("The Head Mistress"), it is 
inadequate ventilation that causes odor.  Aerobic decomposition products 
don't 'smell.'  The problem, according to her, with single line vents is 
that it does not let adequate air flow for aerobic decomposition.

Like several others on this list, I decided to try this strategy, and I 
must say I am a believer.  I installed our head 5 years ago and we lived 
aboard for 3 of those years.  That's four people using one head and one 
holding tank.  Keeping the head itself clean and odor free was more of 
an issue than the tank ventilation.

If you think about it, it's also at least part of the principle behind 
composting heads like the Air Head.  The only difference is that they 
use a fan to force air into the system.

Two vent lines, one on each side, that allows one to be intake and one 
outflow allows for a constant stream of fresh air into the take...and 
aerobic, odor free decomposition in the tank. Decomposition always 
occurs.  Enough air flow = no odor, not enough air flow = a stinky mess.


>
>> Any odors ever waif back from the bow?
>
> Not on deck, anyway.
>
>  - George
>

-- 
John S. Riley
S/V Gaelic Sea
1972 Alberg 30 #521


 1362432382.0