I picked up a boat that had been on the hard for a couple of years. We splashed and found some blackflow into the bowl when the boat is left for a few days. Joker valve was just replaced but we havent been back since. We also discovered that the handle to pump the head would pop back up unless the pump out cap was unscrewed so we had the vent cleared out. The head is only a few years old and the lines were also replaced. The holding tank however, is 30 years old. We are currently using Odorlos as a treatment even though I didn't have the best experience with it on my last boat. I'm curious if we would benefit from something like Noflex digestor or another more intensive cleaning product to clean the old tank or as a preventative measure. The head stinks last time we were on board!
Recommissioning head and holding tank
- Thread starter Project_Mayhem
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No relationship at all.
The holding tank is (should be) completely sealed. The contents, no matter how foul, are not causing the external smell . Look for a leak somewhere else.
If that's still leaking, there's one possible source of odour.
Are the lines a good quality hose.
Many of us have used the head sink drain tapped into the head input so as to use fresh water for the LAST flush before leaving the boat, discussed here many times. The smell could well have come from seawater sitting in the head when you're gone (although your lake is not salt water). So you've got some backup from your holding tank somewhere. How long since you pumped out?
The joker valve was leaking and the vent for the tank was clogged. we have not been back since these items have been taken care of. The hoses are good quality but not top notch. I do not remember the model off the top of my head. Will the contents of the holding tank smell if properly treated?
We're told that the contents of an aerobic (properly treated) holding tank will mostly give off methane and CO2 both of which are odorless.
But I hope you're not looking at odorless sewage as being a solution for your smelly problem
:I don't know if the guests would approve.
O
There are a couple of tank products--NoFlex Digestor is the best, Odorlos is another--that can work with less oxygen than others, but there is no tank product that can prevent odor completely without any.
--Peggie
You're told by WHOM??? Definitely not by me! It's oxygen, not treatment, that creates the aerobic conditions necessary to prevent odor from being created. Methane IS odorless, but is an anaerobic flammable gas. CO2 is aerobic but is heavier than air, so without enough air exchange via the tank vent or an aerator, it can blanket the contents of a holding tank, turning them anaerobic.
There are a couple of tank products--NoFlex Digestor is the best, Odorlos is another--that can work with less oxygen than others, but there is no tank product that can prevent odor completely without any.
--Peggie
Are you recommending Digestor over Odorlos? How would one determine if there's a layer of anaerobic gas, aside from a stinky head which could be caused by a few different issues?
But, but, but, that's exactly what I mean.
The holding tank contents are "properly treated" by the unspoken, the vent lines, which supply air (which is about 21% O2) to promote aeorobic decomposition. There are other means (chemical) of getting O2 into the contents but this is the simplest and cheapest. Cheap is the reason I choose to use vents rather tham chemicals. And speaking of cheap, I always take my eyeglasses off when I'm not looking at anything so as not to wear them out.
And as you say, because CO2 requires a little motivation to keep moving along, dual vent lines are better than just a single vent line :
The forward vent hose is connected to an above the waterline thru-hull at the beam of the boat and the aft vent hose exits at the aft end of the hull which sees slightly negative air pressure while under way.
The holding tank contents are "properly treated" by the unspoken, the vent lines, which supply air (which is about 21% O2) to promote aeorobic decomposition. There are other means (chemical) of getting O2 into the contents but this is the simplest and cheapest. Cheap is the reason I choose to use vents rather tham chemicals. And speaking of cheap, I always take my eyeglasses off when I'm not looking at anything so as not to wear them out.
And as you say, because CO2 requires a little motivation to keep moving along, dual vent lines are better than just a single vent line :
The forward vent hose is connected to an above the waterline thru-hull at the beam of the boat and the aft vent hose exits at the aft end of the hull which sees slightly negative air pressure while under way.
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I put ice cubes and some detergent along with some water and sailed the boat for a few weeks (the ice cubes only work for the first day
). The idea is that the cubes help “ scrub the inside of the tank, detergent and water softener any hard “crap”in the tank. Sail it is as lumpy seas as you can stand!After that, pump out and hopefully the tank is cleaner than it was.
Alternately, I have removed my tank, took it home to rebed the various fitting that were screwed into bosses. A few were leaky, leading to my smelly aft cabin. I removed the fittings, blasted the inside of the tank with pressure washer, got it as clean as I could and reinstalled the fittings. Made a huge difference (probably mostly by fixing the leaks).
Greg
Dual vent lines are NOT the best way to increase air exchange in the tank and chemicals aren't an alternative...a few are just able to work with less air exchange. A single vent will work just fine IF:
a) it's short (no longer than 5-7', straight and doesn't rise more sharply than 45 degrees.
b) the "vent" thru-hull is replaced with an open bulkhead (aka "mushroom") fitting that will let the tank "breathe"..."vent" thru-hulls do not.
Aeration is a much better choice than a second vent and doesn't have to be expensive...many boat owners are DYI-ing aerators using a bait tank pump and a perforated (poke holes in the top of it) piece of hose run across the tank near the bottom of it. To work, aerators MUST run 24-7-365 whether you're on the boat or not, but the current draw is very low. When not running the tank will quickly turn anaerobic, forcing stinky gasses out the vent when it's turned back on that can take several hours to slowly improve.
-Peggie
a) it's short (no longer than 5-7', straight and doesn't rise more sharply than 45 degrees.
b) the "vent" thru-hull is replaced with an open bulkhead (aka "mushroom") fitting that will let the tank "breathe"..."vent" thru-hulls do not.
Aeration is a much better choice than a second vent and doesn't have to be expensive...many boat owners are DYI-ing aerators using a bait tank pump and a perforated (poke holes in the top of it) piece of hose run across the tank near the bottom of it. To work, aerators MUST run 24-7-365 whether you're on the boat or not, but the current draw is very low. When not running the tank will quickly turn anaerobic, forcing stinky gasses out the vent when it's turned back on that can take several hours to slowly improve.
-Peggie
If the holding tank contents stink the odor should only come out of the vent line. The contents of the holding tank stinking should not mean that the head compartment or toilet stink. A la Ralph Johnstone in reply 2. Right?
So if your head compartment smells it is likely leaks in the fittings, permeated hoses, or as Stu said in post 3, stinky dead stuff that has been sitting in the intake lines and toilet bowl channels while you are away and not exercising the toilet pump. Even "fresh" lake water will have organisms that will die and smell when trapped in the intake.
If you flush thoroughly, even small backflow through the joker valve shouldn't cause (much) odor because the backflow should be clean water.
So if your head compartment smells it is likely leaks in the fittings, permeated hoses, or as Stu said in post 3, stinky dead stuff that has been sitting in the intake lines and toilet bowl channels while you are away and not exercising the toilet pump. Even "fresh" lake water will have organisms that will die and smell when trapped in the intake.
If you flush thoroughly, even small backflow through the joker valve shouldn't cause (much) odor because the backflow should be clean water.
I'm happy to report that the new joker valve and cleared vent have reduced the smell by 70-80%!
I looked at Practical Sailor's testing of various products. Is BacTank T3 still available?
I looked at Practical Sailor's testing of various products. Is BacTank T3 still available?
We've been seeing flakes of black stuff whenever freshwater is pumped into the bowl. I assume something dried up or had been growing in the hoses/channels? It's slowly decreasing but it's still there
The toilet plumbing may not be the source....a shower sump in serious need of cleaning can make the head compartment stink. Cleaning it doesn't have to require any manual labor. Raritan only markets their "C.P" as a bowl cleaner--and it's a good one, but it's also the best sump and sink drain cleaner on the planet (I know this because it's part of the product line I developed and sold to Raritan in 1999.)
To clean sumps, fill about half full with water...add 2-3 oz of C.P when it can stand at least overnight (C.P is a bio-active product that needs time to work.) but there's nothing in it that can harm anything, so it can remain in the sump for weeks, even months...it just quits working when it exhausts its food source--about 12 hrs. Next morning or whenever, turn on sump pump to drain the sump and rinse with clean water....job done.
To clean sink drains, close the thru-hull seacock, put 1-2 oz down the drain, fill with clean water and let stand at least overnight. Next morning or whenever, open the thru-hull to let drain and rinse with clean water. Job done.
To clean sumps, fill about half full with water...add 2-3 oz of C.P when it can stand at least overnight (C.P is a bio-active product that needs time to work.) but there's nothing in it that can harm anything, so it can remain in the sump for weeks, even months...it just quits working when it exhausts its food source--about 12 hrs. Next morning or whenever, turn on sump pump to drain the sump and rinse with clean water....job done.
To clean sink drains, close the thru-hull seacock, put 1-2 oz down the drain, fill with clean water and let stand at least overnight. Next morning or whenever, open the thru-hull to let drain and rinse with clean water. Job done.
@Peggie Hall HeadMistress Thank you for the info on the the sumps and drains. I'll take a whiff of the drains to see if they smell. Did you create and sell KO as well?
Questions for everyone:
We noticed a 70-80% reduction in smell after the joker valve is replaced. No one way valve will block all backflow. Three or four check valves are used in some industries to mitigate this. Since this boat is new to me, should the hoses and tank have a more intense treatment added to it to give it a good "cleaning"? What can be done about this flaky black stuff that appears when fresh water is pumped into the bowl?
Questions for everyone:
We noticed a 70-80% reduction in smell after the joker valve is replaced. No one way valve will block all backflow. Three or four check valves are used in some industries to mitigate this. Since this boat is new to me, should the hoses and tank have a more intense treatment added to it to give it a good "cleaning"? What can be done about this flaky black stuff that appears when fresh water is pumped into the bowl?
If your toilet uses sea water, it's buildup of micro and maybe not-so-micro buildup in the toilet intake line and the channel in the rim of the bowl. Replacing the intake line may be the easiest fix for it...cleaning out the channel in the rim of the bowl will require blasting it out via the intake fitting on the back of the bowl and replacing the short piece of hose that connects the pump to the bowl. That can be a messy enough job to make it advisable to remove the bowl and set it on the dock to do, which will also make it advisable to replace the flat bowl seal.
This can be prevented by re-routing your toilet intake line to tee into the head sink drain line below the waterline. This will allow you to continue to flush with sea water, while also providing a safe source of fresh water to rinse the sea water out of the entire system (pouring water into the bowl or using the shower head only rinses out the toilet discharge line): the head sink. To use it, close the sink drain thru-hull and fill the sink with clean fresh water. Flush the toilet to pull the water out of the sink, rinsing the sea water out of the intake line, pump, channel in the rim of the bowl AND the toilet discharge line. No more odor from head intake, no more black flecks in the flush water. You can even flush using sink water instead of sea water all the time if you want to.
Some sailboat builders used to plumb their toilets to use the sink drain 'cuz it saved 'em the cost of an intake thru-hull and seacock...Tartan was one of them. I first heard of this from a Tartan owner in the mid -90s...thought it was such a great idea that I've been recommending it ever since. It does require that the toilet and head sink be on the same side of the keel, however.
--Peggie
This can be prevented by re-routing your toilet intake line to tee into the head sink drain line below the waterline. This will allow you to continue to flush with sea water, while also providing a safe source of fresh water to rinse the sea water out of the entire system (pouring water into the bowl or using the shower head only rinses out the toilet discharge line): the head sink. To use it, close the sink drain thru-hull and fill the sink with clean fresh water. Flush the toilet to pull the water out of the sink, rinsing the sea water out of the intake line, pump, channel in the rim of the bowl AND the toilet discharge line. No more odor from head intake, no more black flecks in the flush water. You can even flush using sink water instead of sea water all the time if you want to.
Some sailboat builders used to plumb their toilets to use the sink drain 'cuz it saved 'em the cost of an intake thru-hull and seacock...Tartan was one of them. I first heard of this from a Tartan owner in the mid -90s...thought it was such a great idea that I've been recommending it ever since. It does require that the toilet and head sink be on the same side of the keel, however.
--Peggie
The sink drain and head intake share the same thru hull and I know there's a ball valve on it so this should be possible. I'm on Lake Michigan so this is "fresh water"
Even Lake Michigan can have coves that can get a bit skanky and the water in every marina is skanky due to runoff from parking lots, dirty bilge water from boats, cleaning products etc etc etc.and you can always pull in a bit of animal or vegetable marine life...so you're not totally immune from intake odor issues.
--Peggie
I bet you his head doesn't stink with this practice! Nothing like flushing your pee with your neighbor's!And my neighbor who is too lazy to walk to the restroom
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I came back to the boat and the smell has reduced by another 10%. It's been about a week since we pumped out. I can see black crap is growing on the inside of the head hoses so that's probably the source of the black flakes. We're making progress!