Bob,

are you actually disinfecting, cleaning or deodorising?

A cup of vinegar, 250 ml of 5% acetic acid.

In, lets say 9 US gal of water , about 34 liters.

That about a 1:136 dilution, ie 34 liters of 0.037% acetic acid.

Certainly wouldn't want to trust that solution to do anything except leave a
slightly "vinegary" scent!

The effective concentration of the acetic acid would be even lower, some
would immediately react with compounds in the water or on the tank, leaving
even less to do any "disinfection".

Bleach, for all of its negatives, does do a good job on clean surfaces
Effectiveness is diminished by among other things, organics, ie dirt.

If you don't want to use bleach, look into the products that dairy farmers
use to clean their equipment. Most, I believe are quaternary ammonium
compounds. I use similar formulations as a bench disinfectant and as part of
my "spill kit", and they do "kill bugs dead" (when used correctly).

The dairy disinfectants (and cleaners and descalers) are designed to be
easily rinsed off and do not harm stainless steel (as does bleach).

Actually some home brewers are using the stuff.

Alistair

(not an expert but I do deal with respectable quantities of pathogens at
work)

on 30/12/02 9:50 AM, Bob Stevens wrote:

> "What concentration of vinegar is needed to act as a disinfectant?"
>
> I use a cup in about 8-10 gallons in the water tank. Let it stay there a day
> or two while I drive it around, then, with the engine running, run a half
> gallon thru the faucet and let it drain in the sink. Cleans the sink and
> drain as well.
>
> Bob Stevens
> '87 Syncro Westy