This Blog by, Boating By Dawsons has great information for boaters. https://www.boatingwithdawsons.com/articles/boating-articles/does-your-holding-tank-really-stink.html
On boats with toilets, builders install a holding tank to hold the sewage until the boat reaches a pump out facility. Some yachts come equipped with a “Y” valve, so that they can choose to pump out or discharge overboard while way out in the ocean. In most of Canada and the United States, it is illegal to discharge overboard and there are heavy fines for doing so. It is advisable to leave the overboard discharge valve locked to prevent accidental discharge and fines.Most holding tanks are plastic, but there are some stainless steel tanks and even a few aluminum tanks still around.
Back in the 1960's, we were involved with the Ontario Marine Operators Association's negotiations with the Ontario Government to introduce the first Holding Tank and Pump-Out legislation in North America. This put a stop to all black water (holding tank waste) from entering the waterways.
Odor PreventionTo prevent odor, there are several things you can do.
- Make sure your holding tank system has adequate air flow. Eliminate any low spots in vent lines that would restrict the flow of air. Aerobic bacteria (the good guys) requires oxygen to live and function.
- Avoid the use of detergent, bleach, dish soap or other cleaners or odor-masking agents in the holding tank.
- If using a head chemical, use one that is formaldehyde and bromine free to allow aerobic bacteria to live and work properly in the tank.
- Change the hoses, seals, gaskets and impellers in your sanitation system on a regular basis and fix immediately if there is a problem.
- Always pump out when you can, before it is full; otherwise, it could overflow and fill the air breather or leak into the bilge and/or back up in the toilet.