Head chemicals

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Can you suggest the amount to use in a 48 gallon tank based on your own experience as to what works? Save me trial and error.
Same amount as for NoFlex. My tank is 45 gallons. I use one tablespoon per poop flush. My tank has minimal sludge when I flush it twice a year, absoultely no solids build-up.
 
A few clues from the MSDS:

Sulfuric acid salt monohydrate
Decomposition products are sulfur and metal oxides
EDTA mentioned as antidote
Molecular weight is 179.47
Boiling point is 740 degrees C, decomposes
Soluble in water
NFPA diamond 2-0-0
Can be used to treat sewage odors

Zinc sulfate monohydrate fits the above points.
Looks like DCDC Dan has solved the "what is it composed of" question.
Does anyone have any info on how the sulfuric acid salt monohydrate works in a holding tank?
Searches turn up no reference to use in sewage treatment as does Sodium per carbonate, the active ingredient in NoFlex.
 
Flushing odor may be coming from your feed hose, especially if you are using raw water. My aft toilet feed line has to run 10 ft from the through hull fitting. It makes a great petri dish for multiple foul smelling organisms. I added a manifold of 2" pipe to the feed line near the connetion to the toilet. it has an in and out fitting reduced to hose size and a 2" screw cap at the end. I put pool chlorine tablets in the manifold at the screw end. NO STINK. But I suspect this would interfere with any digesting addatives you use.
 
Been a Peggie fan and have listened to other cruisers over the years.

Best chemicals is no chemicals.


If your tank has aerobic flora which means sufficient O2 in the tank. And there’s sufficient turnover. And piping is impermeable there should be no smell. We have used this formula for the last decade and it works.
On occasion after the holding tank has been fully emptied will add new bacteria but beyond that go light on additives. Even to the point of only using vinegar to clean the bowl followed by a good fresh water rinse. Will use “Just Science “ on occasion. We do make sure venting is good and open. We aren’t stingy with fresh water flushing. We avoid ever leaving the boat with anything in the tank if we’re going to be away for awhile.That way there’s less time for sludge to settle. Also want just fresh water left in all the pipes to the tank. Chinzing on flush volume can give you troubles. Even after just pee. I think about the holding tank the same way as the house septic system. Difference is you pump out the sludge in a septic system every few years and have a leaching field. Chemicals that kill or change the flora in the holding tank give you troubles. Sludge clogs things. So less is more. After so many troubles with guests have taken to placing small lidded garbage cans next to each head with a paper bag inside. Only excrement goes in the toilet. Not even toilet paper. Paper takes longer to break down even if macerated. Also it allows us to use regular two ply and not be worried about baby wipes. Also not worried about throwing stuff out once outside 3m limit. Inside the limit keep a sealed plastic garbage bag in the lazerette so no smell or difficulties. Put the paper bags in there.
A good head system should require little or no attention. Like engines may get into trouble with lack of use. If we are having even a hint of troubles will pump out. Fill 1/2 full, leave stabilization off and go for a bumpy ride. Then pump out again. Now you’re starting fresh. Set up good flora and no troubles.
 
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Agree that no chemicals is best. After putting in a Sweetank we didn’t add chemicals for the 8 years that epwe owned that boat.
 
Hippo, I agree with most of what you say in your post, but keeping used toilet paper in paper bags is not necessary with today’s marine heads. I would be cruising alone if I told my wife and/or guests that was necessary on our boat.

Do the dissolve test on the TP you buy (I’m sure you’ve seen Peggie’s instructions) and flush away. We tell our guests that wet wipes are death to marine heads and to go light on TP quantity and you should be fine. We’ve been doing it that way with multiple boats over quite a few years.

Occasionally someone would get carried away with the amount of TP and a head would not want to flush. Waiting a few minutes for the paper to dissolve and flushing it again would solve it 99% of the time. As you said, chasing it with plenty of water helps the whole system work better. The only times we have had clogs that actually needed fixing was due to wet wipes or some other trash, never just TP.

You have a nice boat and I’m sure you have good quality heads in there. Try letting the heads do their thing and you might find you like the upgrade.
 
If you store used wet wipes in a lidded container pending trash disposal it`s no great leap to store used TP as well. Perhaps the deodorizing function of wet wipes prevents the co mingled materials from emitting malodours.
 
We have not used the TP in the garbage can procedure but have friends that don’t flush TP. They say they get no smell due to the TP in the garbage can.
 
Some folks and a lot of kids cause clogs. Don’t know why they’ll use 1/2 a roll but they do. I don’t want a awkward interaction. Also people stick things other than TP in there. So think the rule is simple, clear and avoids troubles. Lastly dissolving isn’t digesting. Cellulose is a pretty indigestible fiber for the flora in your holding tank. We are often outside the dump limit so keeping the exhaust through hull and hose clear is important to us. It’s those clogs that are troublesome particularly if you’re in cold waters. Have found best way to clear them is an old time plumbers helper applied from the outside.
So TP can dissolve instantaneously in the air for all I care but I’ve found with our simple rule I’ve stopped needing to deal with clogs QED.
 
Some folks and a lot of kids cause clogs. Don’t know why they’ll use 1/2 a roll but they do. I don’t want a awkward interaction. Also people stick things other than TP in there. So think the rule is simple, clear and avoids troubles. Lastly dissolving isn’t digesting. Cellulose is a pretty indigestible fiber for the flora in your holding tank. We are often outside the dump limit so keeping the exhaust through hull and hose clear is important to us. It’s those clogs that are troublesome particularly if you’re in cold waters. Have found best way to clear them is an old time plumbers helper applied from the outside.
So TP can dissolve instantaneously in the air for all I care but I’ve found with our simple rule I’ve stopped needing to deal with clogs QED.

What is your simple rule?
 
If it didn’t come out of you it doesn’t go in the head.

There’s a can next to it. Throw it there.
 
We have not used the TP in the garbage can procedure but have friends that don’t flush TP. They say they get no smell due to the TP in the garbage can.

I've traveled in several countries where it's customary to put TP in small trash can next to toilet. Surprisingly, there is no odor. I'm not a fan, but "when in Rome...." That said, i think Americans in general are a bit overly touchy about topics like these.

Peter
 
Some folks and a lot of kids cause clogs.

When I put in a septic system at home, I asked the installer/repair guy what I needed to watch out for. He told me "teenage girls" and said that I wouldn't believe what they would flush. I didn't ask for details.

I've travelled plenty where the facilities have the little trash can next to the toilet. Never been a problem for me, but I have no idea how many days one gets out of that system. For those boaters travelling from marina to marina, not an issue. But I don't know about 10 days without shore-side disposal. The old school "burn on the beach below the high tide mark" always seemed like a bad idea and is likely now illegal.

I'm reminded of what the Water Rat said: “Believe me, my young friend, there is nothing–absolutely nothing–much more disgusting than messing about with a boat's clogged head.” That quote was left out of the Wind in the Willows.
 
We’ve been putting Scotts marine/rv tp in the head for 13 years of live aboard. Never a problem. Just suggesting throwing used tp in a trash can would have my family buying a house.
 
We’ve never had a problem with me and the bride. It’s other family and guests. It’s a unpleasant conversation so said once to all aboard. Nothing ruins the experience for guests than having me distracted by clearing a head. People talk about wanting two engines. For me having two heads is equally important.
Have been through the two teenage daughters. Even the two teenager daughters and their giggly friends. Have done passage where it’s three women and me. Some guys are just as bad. Have picked out the shaving blade protectors, hair rubber bands, contraceptives and all kinds of stuff. No thanks. The rule stands and no troubles for over a decade. BTW we use regular old TP.
TP in a paper bag inside a lidded garbage can gives no smell. Bag gets 1/2 full roll it up goes into a plastic garbage bag in the lazerette if coastal. If mid ocean goes over board. After all it’s biodegradable. Not a biggie. I even have no issues wiping my grandkids bum and with this program you’re never touching anything nasty.
 
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We try to set rules for proper head etiquette for guests aboard our boat. One thing we tell them is if they make a mess in the head they need to clean it up. We were patrolling a Tall Ships event and had a couple aboard. After they departed the boat we found that he had left extraordinary skid marks in the head. There were cleaning supplies next to the head but he didn’t bother. They called several times later asking to patrol on our boat, but coincidentally we never had any room for them. I always tell people to treat others boats better than they would treat their own boat.
 
We were patrolling a Tall Ships event and had a couple aboard. After they departed the boat we found that he had left extraordinary skid marks in the head. There were cleaning supplies next to the head but he didn’t bother.

A problem easily prevented by providing instructions on head use that, along with "how to flush," include adding water to the bowl ahead of solids to guests who may not have had any experience with marine toilets.



--Peggie
 
We have not used the TP in the garbage can procedure but have friends that don’t flush TP. They say they get no smell due to the TP in the garbage can.
I dont subscribe to that but don't see a problem for those that do. Think about it... the key to a non-smelly holding tank is plenty of air... just the situation with TP in "open" air. I'm assuming aerobic bacteria prevail and anaerobic don't stand a chance.
We do not flush wipes at home, aboard or in our motorhome... never been a smell problem.
 
We were patrolling a Tall Ships event and had a couple aboard. After they departed the boat we found that he had left extraordinary skid marks in the head. There were cleaning supplies next to the head but he didn’t bother.

A problem easily prevented by providing instructions on head use that, along with "how to flush," include adding water to the bowl ahead of solids to guests who may not have had any experience with marine toilets.



--Peggie

Oh, we did explain that. But apparently he couldn’t learn.
 
Peggy, trying to reach you on PM basis via phone or text. Like to chat on speaking opportunity mtoa . Thanks.

Bill gillroy
MTOA. AGLCA
678-221-7486
 
Hi Bill...just left you a VM. Looking forward to talking with you.



--Peggie
 
oops, i was on page 1, not 3 of the thread, it looks like others already found all of this info.



all i did was google
happy camper holding tank treatment msds
first link was this:
https://www.happycampersworld.com/wp-content/uploads/2017/11/MSDS.pdf


so there is your MSDS, but you're going to be disappointed.



That msds is nearly useless as it lists the contents as: 'monohydrate'. This is because there are not any 'dangerous' chemicals in the mix, so there is not much that needs to be put on the msds.



Some other digging suggests that this chemical might be zinc sulfate monohydrate, but thats a pure guess on my part.
 
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I suspect that many people have lost the aerobic function of their tank vents to mud daubers.
 
Then how would they pump out?
Mud dauber nests are not usually impervious or block the entire passage. Under pump out suction air can come in through the vents or probably through the head. The only indication may be slow pump outs. The problem is that small changes in pressure will not cause enough air exchange and therefore deplete the oxygen levels in the tank.
 
Apparently you haven't had much experience with mud daubers--at least those we have in the South. Their nests CAN completely block a vent line, resulting a pressurized tank and the inability to pump out more than a gallon or two before the pumpout pulls a vacuum that prevents it from removing any more. A particularly strong pumpout can even implode a tank. But before that happens, opening the deck pumpout cap will result in a geyser than onlookers usually find entertaining.

And not just vent lines...I remember getting rid of one in the Venturi pipe in the gas grill on my boat during spring recommissioning. The following weekend I couldn't light the grill...the d'd critters had built a new one!

But mud daubers aren't the only thing that can completely block a vent line. Repeatedly overflowing the tank out the vent will cause waste to build up in the thru-hull and the other end of the vent line--that end of the hose and the vent fitting on the tank.

Replacing the "vent" thruhull with an open bulkhead fitting won't prevent vent blockages but does allow you to prevent them by putting a hose nozzle against it to back flush the vent line every time you wash the boat. This won't relieve you of the need to scrape out a mud dauber nest, but does prevent the buildup in the vent line and flush out any other critters that have set up housekeeping in it.

--Peggie
 
A fifty gallon sewage tank is pretty large. Are you sure you are emptying it enough?

pete
 
Apparently you haven't had much experience with mud daubers--at least those we have in the South. Their nests CAN completely block a vent line, resulting a pressurized tank and the inability to pump out more than a gallon or two before the pumpout pulls a vacuum that prevents it from removing any more. A particularly strong pumpout can even implode a tank. But before that happens, opening the deck pumpout cap will result in a geyser than onlookers usually find entertaining.

And not just vent lines...I remember getting rid of one in the Venturi pipe in the gas grill on my boat during spring recommissioning. The following weekend I couldn't light the grill...the d'd critters had built a new one!

But mud daubers aren't the only thing that can completely block a vent line. Repeatedly overflowing the tank out the vent will cause waste to build up in the thru-hull and the other end of the vent line--that end of the hose and the vent fitting on the tank.

Replacing the "vent" thruhull with an open bulkhead fitting won't prevent vent blockages but does allow you to prevent them by putting a hose nozzle against it to back flush the vent line every time you wash the boat. This won't relieve you of the need to scrape out a mud dauber nest, but does prevent the buildup in the vent line and flush out any other critters that have set up housekeeping in it.

--Peggie

Thanks Peggy. My vent tube is not easily accessible. I had my holding tank replaced a few years ago, not sure they replaced the vent tube, I suspect not. Had I known I would have insisted. What's the best way to know that it's clear w/o physically removing it? Should I check airflow when flushing or during pumpout? Thanks for your expert advice as always!
 
Most of the OEM vent hoses are not nearly large enough to allow enough air into the tank to prevent anerobic bacteria from growing. The best setup is to have a large vent going to each side of the boat to allow air to flow through the tank. I have a 50 gallon holding tank in our current boat. I added two 1.5” vents, one to each side of the boat. That way no matter which side of the boat the wind is blowing air will flow through the tank.
 

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