Smelly Heads

[VicS]

If you just put seawater in a bottle with no air and leave it, the sulpide smell will not develop.


Richard

That is my experience too. At least storing bottles of clean sea water but maybe the water in popular mooring areas, especially in marinas, might not be so clean/ unpolluted.

 

[Hydrozoan]

... At least storing bottles of clean sea water but maybe the water in popular mooring areas, especially in marinas, might not be so clean/ unpolluted.

Quite! As you know, to generate H2S one needs a food source of organic carbon for the anaerobic bacteria. That could be faecal matter, but it could in principle come from other sources – e.g. dead plankton in the water, or humic/fulvic acids from land runoff.

I did say I might repeat Vyv Cox's experiment storing bottles of clean Aegean seawater (no H2S produced, in my view probably because there was insufficient organic matter and/or bacterial ‘seed’) using an organic-rich UK estuary water to see if natural organics could be sufficient, but I haven’t yet had the opportunity. If somebody else is moored in a suitable spot, they might care to try it ...

PS to thinwater: It’s ‘facultative’ not ‘facilitative’ anaerobes I believe: just means they can use oxygen if it is available.

 

[thinwater]

... If you just put seawater in a bottle with no air and leave it, the sulpide smell will not develop.

Actually, this is not generally true. There is something wrong with your expereiment. It does depend on there being some bacteria present to seed the process, which there always will be in the plumbing. BTW, the bottle must be in the dark. Google any seawater aquarium site--stored seawater gets stinky. It has happened to me with jugs for seawater aquariums every time they have set for more than 2 days.

As for urinal blocks, do what you like. I do not believe you will find a head manufacture that will condone the practice. If you want less stink, they will suggest freshwater flushing.

 

[johnalison]

I assume that you're not talking about the inlet hose from the seacock, which I believe the previous posts are referring to, as you can't put a syphon break vent in that one so can't introduce any air.

Richard

Yes. Between the pump and the loo, ie, the loo inlet, not the boat inlet.

 

[RichardS]

Yes. Between the pump and the loo, ie, the loo inlet, not the boat inlet.

I think you'll find that that hose probably self-drains into the bowl, certainly on a system like mine where it is just a short pipe from the pump to the bowl, so it's presumably not responsible for the smell as it does not contain standing water.

Richard

 

[RichardS]

As for urinal blocks, do what you like. I do not believe you will find a head manufacture that will condone the practice. If you want less stink, they will suggest freshwater flushing.

All the toliet manufacturers recommend using disinfectant to disinfect their toilets. Some even sell their own brand as well as inline dosing devices which do exactly the same the the urinal blocks ..... with the differnence that the urinal blocks subject the toilet and its components to a minute dosing (probably a few tens of ppm judging by how long the blocks last) rather than a massive dosing on an irregular basis.

Which you think is better for your system is down to personal opinion ..... but the toilet manufacturers support both approaches.

Richard

 

[thinwater]

... PS to thinwater: It’s ‘facultative’ not ‘facilitative’ anaerobes I believe: just means they can use oxygen if it is available.

Correct, I'm always spelling that wrong.

The point folks are missing is that the plumbing itself contains organic material and marine life on the walls. It is never pristine, at least a bio-film, so the required bacteria and organics are always there. Add to that that most forum posters anchor in a marina somewhere, and the conditions for stink are nearly always present.

 

[Hydrozoan]

... The point folks are missing is that the plumbing itself contains organic material and marine life on the walls. It is never pristine, at least a bio-film, so the required bacteria and organics are always there. Add to that that most forum posters anchor in a marina somewhere, and the conditions for stink are nearly always present.

Sure; of course, cross-contamination between the outlet and inlet sides (externally, or through a worn pump) could be a cause of odour, but as you say there could be other sources - both of anaerobes and of organic matter.