Nasty smell from holding tanks

[jimbo]

I know this is a much covered subject but I am looking for some new ideas. I have a Jeanneau SO 439 blt 2014 and the holding tanks have started to smell. I use Odourlos throughout the season, plus the occasional flush with a household toilet cleaner. Prior to the new season, I left 5 litres of cleaning vinegar in the tank and associated pipework for a week to clear any scale build up, otherwise the tanks were left empty over the winter. The intake pipes have been cleaned with a pipe ceaning brush (and toilet cleaner) so there is no rotten egg/sulphurous smell when pumping in water. Nevertheless, during the first sail of the season, there was a particularly nasty holding tank smell especially when the boat heeled over with the seacock for the tank open (water sloshing in/out and exposed to the air). Any suggestions for what I can put in the tanks that will remove this residue that is causing the smell? There is an access hatch to the plastic moulded tank from the shower area but I have read horror stories of the hatch breaking when force is applied to open it - it seems they have been sealed with an adhesive and now set rock solid, so physically getting in there and giving it a scrub is not an option.

Appreciate any suggestions

 

[PCUK]

No smell filter?

 

[Sianna]

we had the same on our Leader 805, tried the small purytec inline sanitiser, they didn't work then bought the Sea Smart, I wouldn't say it's 100% but the smells have pretty much all gone, it is worth the £110 we paid at the boat show for it and it took about 15 mins to install.


SeaSmart Marine Ltd | SeaSmart Marine Toilet Sanitiser Systems

 

[Tranona]

Check that the hoses are sanitary grade butyl. Older style hoses are slightly porous and impossible to get clean. Most likely culprit is the outlet hose as that holds the waste when you have the seacock closed to use the tank.

 

[Bilgediver]

Any suggestions for what I can put in the tanks that will remove this residue that is causing the smell?

Appreciate any suggestions

This is precisely the situation that Odorlos was formulated for and I believe it even has the Headmistress seal of approval. Might need a heavy first dose to get the bugs doing their job with the correct follow up doses to keep the air sweet when heeled and upright.

By the way. Be careful of using certain domestic toilet products as they can kill the good bugs and make the smell worse.