Holding tank tips and advice please

[virtualburton]

Hi everybody, I am new to living aboard and using my holding tanks on my Sun Odyssey 469 on a regular basis. I previously had a 41‘ power boat, but we had a full sewage treatment plant on that boat so didn’t have to pump out as often as living aboard this boat with two people.

I have used the pump out at the local fuel dock a couple of times now, but I am interested if anyone has any general specific advice about pumping out the holding tanks on Jeanneaus.  Because the tanks on my boat are 80 L each and taller than they are wide, it seems that the pumpout may not be getting everything… with the flashlight in my phone I can shine it through the side of the tanks and see the level and there appears to be a bit left (approx 3-4”) at the bottom of the tank after pumping out. I have been filling the tanks with water and pumping it out, essentially rinsing them 3-4 times after each pump out, but wanted to check to see if I’m doing it correctly.
I’m also curious to know what you guys do for general treatment. I have shock and deodorizer, but I’m curious to know what people do to maintain their tanks and keep them clean.

Any input or advice is welcome - thanks in advance

*Mods - apologies if this is in the wrong place… it’s not really model specific and isn’t about specific equipment per se so I put it here. Please move if incorrect. Thanks. 

David

[rene460]

Hi Virtualburton, General topics seems the appropriate place to me, it is certainly where I would start looking for posts on this topic.

As a lake sailor, I also use the holding tank and pump out all the time.  I have to agree that for this situation, a larger tank would be useful, but we just get used to pumping out regularly.  I guess people who only attend a confined area occasional or overnight before returning to sea feel it takes too much space.

The pumpout facility uses a vacuum pump in the shore based facility to empty your tank.  Your tank has an internal pipe as part of the pumpout outlet that reaches down to near the bottom of the tank, and the vacuum cannot remove anything below the lower end of the pipe.  If the pipe goes too near the bottom, it becomes blocked more easily, while if it does not go low enough, it leaves too much behind.  Another area where the designer has to find a compromise.

Your procedure sounds pretty much the same as mine, including pumping about 50 strokes of clean water into the tank and pumping out again while it is still connected.  The facilities in our area have a short transparent section in the hose where it connects to the pump unit, and we judge by the colour of the water whether we need one more rinse.

We then use a holding tank additive.  It is locally made, so not much help to you, but it claims to have a biological action to actively break down the waste.  I assume something will be available to you as well.  Look for biological action to promote breakdown in the label.  It is more expensive to buy than the typical blue or green coloured solutions, but requires a much smaller dose so is about the same cost to use.  After each pump out I add the necessary amount via the toilet.  It seems to work very well, on the basis there is no visible solids or paper in the sight glass as we pump out.  My sister in law won’t use it because it is brown, but as far as I can tell, it actually works better than the ones which rely more on sterilisation.  I don’t know what difference the colour of the holding tank contents makes to her.  We have never had any problems with odour, and make no special provision or precautions.

So long as you pump out and rinse first, there is very little in the outlet pipe that is hard to know whether it is reached by the treatment, but could be emptied into a drum in the yard if you wanted to.  

In summary Your procedure sounds pretty good to me.  

rene460

[virtualburton]

Great info and thanks for the verification René. Unfortunately (or maybe fortunately??) the pump out at my marina does not have a clear section so I can’t see the colour of the water/waste but I flush it several times then assume it’s good. Thanks also for the information about the suction hose going down into tank. I didn’t know that so it’s helpful.

I think the previous owners may have left some waste in the tanks for a lengthy period before I got the boat, so it may require some unpleasant cleaning but for now I will monitor the flushes and try to get it as clean as I can.

I do notice some mild odour when sitting at the salon table in the galley. I have checked all the hoses and fittings for both heads and see nothing loose and no signs of anything spilled, so am wondering if the odour is venting to outside via the vents then coming back in… although I don’t seem to smell it outside. 

Any other thoughts or tips are welcome.

Thanks/Merci!

David

[bereboot]

On a former boat without a holding tank, I also had odours that appeared after changing the flexible conduits from the toilet with santiary hose.
So we discovered that even the standard mounted pipes are not completely odour proof.

We changed the pipes again, and afterwards the problem was solved.

This is the rght one: 

www.josboone.nl/recreatie/motor-en-techniek/slangen-en-fitwerk/vuilwaterslang/vetus-sanitair-slang-38x49mm-wit-geurdicht-per-m

[rene460]

Hi David, the one time we get some odour is when we use lake water for flushing and some is left in the inlet hose.  My understanding is that it is the decomposition of the algae which is present in the water, which happens in the hose without sufficient oxygen.  I understand it is no better in boats on sea water.  Once the water is in the holding tank, there is air, and air is mixed in when the next flush arrives at the top of the tank and splashes in.  And the air is replaced in full every time you pump out.  And it seems to be working so far.

The last few years, I have left the lake water inlet closed, and flushed using fresh water via the shower hose.  No plumbing mods required and no possibility of getting foul water into our fresh water system.  And no odour.  Our hoses are still original, so it’s keeping fingers crossed time.  I also use lake water for the extra flushing at the end of pump out, but follow the last one with fresh water, rather than use our fresh water for the whole lot.

We usually only flush the tank twice with 50 pump strokes after pumpout.  Very occasionally three times, possibly at the first time after a time away from the boat.  I think if you are now using the boat very regularly, three or four flushes will eventually move any residue in the bottom from the previous owner, particularly if you can find one of the chemicals with biological action.

rene460

[moonshadow]

I would suggest reading Peggy Hall’s book on preventing boat odors. Cheap from Amazon. Lots of good tips there on holding tank systems. Sunscreen the natural bacteria that lives in the tank is supposed to be a part of the anti odor process I tend to avoid anything that might kill them, like bleach.
When I pump out my tank I will sometimes flush a bit of tide laundry detergent through the system and let it slosh around a bit then pump that out. So far that seems to work ok and doesn’t seem to cause any problems. My thought is that it might break up some of the residual crud and it also smells pretty good.

[virtualburton]

Awesome info guys, thanks so much. I’ll check out that book and will check the hoses from the heads… they are the original hoses that were installed by Jeanneau so am assuming they are the correct type, but will check.

many thanks,
David

[virtualburton]

Quick update - I have now removed all of the panels/decks and examined the holding system in detail and have no leaks of any kind, not even a drop or anything small. This is good!

the bad news is I still have the odour issue. It’s not terrible, but is noticeable if you spend a lot of time a board like I do. I have concluded it’s coming from the aft holding tank gravity drain and seacock. As I said, there are no leaks, but the smell is from there so I disagreeumption was it is coming from the hose as bereboot suggested. 

BUT! 

I checked the hose type and it IS marine holding tank odour proof hose. Here’s a photo of what is written on the side of the hose (it says Merlett Vacupress Waste Odourless):



This photo is a hose on the top of the tank, but the drain hose has the same writing on it. It’s also bigger.

So at this point I’m not really sure what to do. Replacing the hose is going to be a messy job and I’m not sure how I could contain the effluent. Where I live we are not allowed to discharge so don’t have many options other than hauling it out and doing it on the hard I guess.

Anyway, just wanted to post an update. In the mean time I have a deodorizer and will ponder what to do next.

David

[dbostrom]

Unfortunately (for us, not hose manufacturers) even good (Trident, etc.) sanitation hose will eventually perfuse. The process is slower than with plain flexible PVC sanitation hose but is still steady and inexorable. 

If you run your finger or a very slightly damp rag over suspect hose sections, it's possible to confirm leakage by your nose. 

The root cause of perfusion could be solved with a layer of aluminum foil in the tubing, as with food packaging, automotive fuel tanks etc., but for whatever reason is not a method adopted for this particular material no matter how far up the food chain the tubing is.

Replacement with "hard" tubing as found on shore is a permanent fix that can be applied at least in sections and will reduce the total hose maintenace burden. How much flexible gets replaced is in part a matter of patience and mechanical scope to fit in 45s etc. 

We replaced the large exit tube in our 39i five years ago with Trident hose and so far it's not yet perfused. But when(!) the day comes, yes it's for haulout. 

Good opportunity to replace thruhull and valve with actual bronze, so at least there's that. 

[virtualburton]

Awesome, thanks for the info. Sounds like this is fairly common, especially with gravity drains because there is effluent in them all the time.

I looked for odourless waste hose, but these are 60mm ID/70mm OD I think and I could only find 1 1/2”. Does anyone know where I could get the large hose in North America?

thanks,
David

[dbostrom]

It's a strange thing. I know I did the large section with Trident a few years ago but they no longer seem to offer larger than 1 1/2".  Meanwhile I replaced the suction-dump line of same size on another head with "Great White" (another 'premium') brand about 3 years ago and that also does not seem to be available. 

Might have to use exhaust hose,though it's not quite right for the application permeability-wise or so I've read. 

[Seagem]

The rule on my boat is nothing goes down the toilet unless you have eaten it first! Toilet paper goes in scented nappy bags (diapers), which then go in a small pedal bin in the heads. Much less chance of becoming blocked.

[moonshadow]

Also if you are using the air conditioning check the drain pan for smell. On my 469 I thought the smell was from the holding tank dump valve but the condensation pump had failed and water stayed in the area with the A/C. The air return picked up the smell and blew it with cold air into the salon right near the holding tank dump valve.
And I believe Peggy’s book describes good and bad bacteria in the tank. It’s not a good idea to kill everything.
Smells are very frustrating and I am sure there is better hose than Jeanneau used. Keep us posted please on what you end up with.

[kenjen469]

Jumping in here as well. I am the owner of a 2013 469 since March of this year. Same odor problem when sitting on the settee. Seems to me the oder is coming from the drainage hose and or Marelon valve. Hauling out the boat next week to have all through hulls and valves replaced with silicone bronze and want to change the drainage hoses for both heads. Cannot not find the specific 50 mm (per 469 owners manual) sized. Anyone know of a source in the U.S.? Preferably in San Diego?

[virtualburton]

Hi Kenjen,

As a quick update, I removed my 50mm / 2" drain hose hose from the aft head and it definitely was permeated as the folks above described and that has solved the smell problem. Finding the hose in North America is a real challenge though... I was able to find some through my Jeanneau dealer, but make sure to order the drain hose which is 50mm as you noted, the other hoses (vent etc.) are 1 ½".

It actually wasn't that difficult to remove - I removed the settee seat backs and the hinged seat base above the valve, then in the head I removed the access panel, unscrewed the panel below and I could access the double clamps on both ends. The hose was exactly 36" long and the valve looks and smells fine to me - seems it was just the hose.

The challenge is there is no valve on the bottom of the holding tanks, so those discharge hoses are always full of raw sewage and when pumping out through the deck fitting it doesn't pull it up out of the drain hose, so it just sits and permeates. I guess it's not that tough to replace the hose... the aft one at least, but it's a dirty stinky job and the bilge needs a thorough clean after removing the hoses so bear that in mind if you do it yourself. It's worth flushing fresh water through that hose whenever you legally can. For me I have to pump out all the time so will be doing it in another 7 years I guess. 

Best of luck to you. I have found that other than this issue, she's a lovely boat and I'n super happy with mine, I got her in June.

David

[kenjen469]

David, thanks for the reply. This is very helpful. I do the pump out routine of filling and pumping until I see clear water through the pump out hose glass. I did remove and replace the toilet-to-tank hoses. They were completely calcified. Weighed a "ton." Also replaced joker valved and the secondary one way in-line valve. Will be hauling out on Thursday to get the big job done on the hard. Painting, through-hull updates, and sail drive service.

I also converted to a fresh water system recently using this process: 
Worked wonders and completely eliminated odors emanating from the toilets, valves, and hoses leading to the holding tank.

My wife and I love the boat. Outfitting it now for extended cruising down the Mexican coast and beyond.

Ken

[virtualburton]

Sounds excellent Ken, thanks for the video too. David

[jy51]

Jul 24, 2021 18:55:05 GMT virtualburton said:

Quick update - I have now removed all of the panels/decks and examined the holding system in detail and have no leaks of any kind, not even a drop or anything small. This is good!

the bad news is I still have the odour issue. It’s not terrible, but is noticeable if you spend a lot of time a board like I do. I have concluded it’s coming from the aft holding tank gravity drain and seacock. As I said, there are no leaks, but the smell is from there so I disagreeumption was it is coming from the hose as bereboot suggested. 

BUT! 

I checked the hose type and it IS marine holding tank odour proof hose. Here’s a photo of what is written on the side of the hose (it says Merlett Vacupress Waste Odourless):



This photo is a hose on the top of the tank, but the drain hose has the same writing on it. It’s also bigger.

So at this point I’m not really sure what to do. Replacing the hose is going to be a messy job and I’m not sure how I could contain the effluent. Where I live we are not allowed to discharge so don’t have many options other than hauling it out and doing it on the hard I guess.

Anyway, just wanted to post an update. In the mean time I have a deodorizer and will ponder what to do next.

David

Try tightening up all jubilee clips, on the hoses, they work a little loose over time and can contribute towards bad smells.

[virtualburton]

Thanks - I checked them all in the beginning. The smells were definitely from permeated hose. Once I removed it the smell went away. 

I got a membership at spareparts.jeanneau.us

and I found the 2"/50mm hose available under this part number:

064182

HOSE SANITATION D51 WHITE

Hopefully this helps someone in the future.

David

[rxc]

You might look into the availability of Great White Sanitation hoses up in your part of the continent, to save on shipping from the east coast of the US. I bought 8 ft of the 2 inch hose from a supplier down here in FLorida who is only an hour south of me, but the only other suppliers I could find were in California and Washington State (Fisheries Supply in Seattle). It might even be cheaper for you to take a drive down there to pick it up.

Shipping from the west coast would have been more than the cost of the hose.

[fma]

Jul 22, 2021 16:06:36 GMT virtualburton said:

Awesome info guys, thanks so much. I’ll check out that book and will check the hoses from the heads… they are the original hoses that were installed by Jeanneau so am assuming they are the correct type, but will check.

many thanks,
David

Another vote for Peggy Hall's book, and I've been using one of her products KO (now made by Raritan) for many years with great results. I'm just about to swap all the hoses and heads along with conversion to fresh water flushing to address "odor" (got to keep the admiral happy).  Quick way to check your hoses is wrap a hot cloth around them and once cool remove and smell the cloth for odor.

[robert1]

Going trip always needs toilet paper. So, I highly recommend Scott toilet papers. This TP changes the RV game in a big way. We spend a lot of time in our RV and this TP is the very best that we have ever used. And it's very soft and absorbent; I don't even recognize any difference.

[NZL50505]

Not sure if this has already been discussed (I couldn’t spot it) but what about the breather pipe / valve?

Reason for asking, a few weeks ago we noticed a strong smell every time the toilet was flushed (the smell was outside the boat ie if we were underway it wafted back towards the cockpit). Somebody said to me that these tanks have a rubber breather valve that is supposed to be one way but it becomes stiff with time and doesn’t seal properly? This sounds plausible but since we’ve been in NZ lockdown last few weeks I haven’t had chance to even look for such a valve let alone inspect?

Anyone know?

[Don Reaves]

Sept 22, 2021 20:24:47 GMT NZL50505 said:

Not sure if this has already been discussed (I couldn’t spot it) but what about the breather pipe / valve?

Reason for asking, a few weeks ago we noticed a strong smell every time the toilet was flushed (the smell was outside the boat ie if we were underway it wafted back towards the cockpit). Somebody said to me that these tanks have a rubber breather valve that is supposed to be one way but it becomes stiff with time and doesn’t seal properly? This sounds plausible but since we’ve been in NZ lockdown last few weeks I haven’t had chance to even look for such a valve let alone inspect?

Anyone know?

If you're referring to the vent, which allows air to move between the tank and the outside, it's been mentioned. I'm not sure why there would be a one-way valve. You would need to let air out when you flush, and in when you pump out. There may be a filter in the vent line that prevents smells from leaving the boat, though my boat doesn't have one. In this case, a one-way valve might be used to bypass the vent, allowing outside air in, but I've never read about anyone providing one.

[moonshadow]

After a pump out try flushing a bit of tide laundry detergent and fresh water into the tank and hoses. I don’t remember where I read this but it helped mine a lot.