I just installed a Thetford 550p Porta Potti with MSD hoses in my Capri 22. When the time comes to launch the boat I want to have the Potti ready to go. What additives should I add to the fresh water tank and or the waste tank?
First time Porta Potti owner/user : question
- Thread starter Sail22Capri22
- Start date
All you want in the waste tank is Odorlos, or another product that supplies oxygen - that will eliminate odor. Really, eliminate it.
Not sure what you mean by fresh water tank. When we open the bowl of our MSD, the waste tank is right there. So waste goes directly into the waste tank without any need for flush water. While our bowl is plumbed for fresh flush water, we never use it. It just takes up waste tank capacity without serving any purpose. If you want to use flush water, fresh tap water is the best. No additives needed. Sea water is a no-no as it will add lots of interesting smelly organisms.
Our MSD is probably original equipment on our boat. In any case, it has served us well for 24 seasons without any repairs! Capacity for the two of us is 4-5 days, and pumping out is easy and quick.
Not sure what you mean by fresh water tank. When we open the bowl of our MSD, the waste tank is right there. So waste goes directly into the waste tank without any need for flush water. While our bowl is plumbed for fresh flush water, we never use it. It just takes up waste tank capacity without serving any purpose. If you want to use flush water, fresh tap water is the best. No additives needed. Sea water is a no-no as it will add lots of interesting smelly organisms.
Our MSD is probably original equipment on our boat. In any case, it has served us well for 24 seasons without any repairs! Capacity for the two of us is 4-5 days, and pumping out is easy and quick.
Thanks for the reply! When I mean fresh water I mean the tank that supplies water when you pump before/after (?) a flush
There are a little bottles of blue stuff you can buy from West Marine but if you spill it stains everything. I always add a cup of Pine-Sol to mine with regular water
You don’t add anything to the freshwater reservoir.
For the holding tank, I have gone to using Noflex Digester. This product not only controls odor well, but it also eliminates sludge in the tank and in the lines. Odorlos is another good product.
The "water tank" is the flush water reservoir in the potty.
Odorlos Odorlos --available from RV supply stores for a lot less than marine store prices--is a good choice for the tank. Because MSD potties are vented, the toxic chemical tank products will only add a chemical odor to any sewage odor. The tank should be rinsed out every time it's pumped out... easily done with a bucketful of water during pumpout.
--Peggie
Odorlos Odorlos --available from RV supply stores for a lot less than marine store prices--is a good choice for the tank. Because MSD potties are vented, the toxic chemical tank products will only add a chemical odor to any sewage odor. The tank should be rinsed out every time it's pumped out... easily done with a bucketful of water during pumpout.
--Peggie
What Peggy said. (For newcomers, Peggy is the wonderful expert on all such questions - truly our Head Mistress!)
We rinse our MSD waste tank by holding a hose of fresh water over the pump-out fixture until the Admiral who is inside says stop - then we pump out again, and repeat, rinsing twice.
Again, our bowl is separated from the waste tank below by a simple kind of trap door. For bowel movements, we open the trap door and and the excrement just drops into the waste tank. Same with the soluble toilet paper. So no flush water is needed. Flushing just causes the waste tank to fill up quicker, so its your choice.
We rinse our MSD waste tank by holding a hose of fresh water over the pump-out fixture until the Admiral who is inside says stop - then we pump out again, and repeat, rinsing twice.
Again, our bowl is separated from the waste tank below by a simple kind of trap door. For bowel movements, we open the trap door and and the excrement just drops into the waste tank. Same with the soluble toilet paper. So no flush water is needed. Flushing just causes the waste tank to fill up quicker, so its your choice.
I disagree with you, David, about no need for flush water...solids and TP need it to dissolve in the tank--urine alone just isn't enough-- and skid marks (I don't care how careful you are to aim for the trap door, you're gonna miss occasionally) in the bowl. The pumpout line needs it too. You only need a cupful...a five gallon tank is rated to hold 50-60 flushes, and that's WITH enough flush water to rinse the bowl--which putting water into the tank via thed pumpout fitting can't do.
--Peggie
--Peggie
Agreed on skid marks.
Weighing 24 seasons of 20-25 nights or more on the boat and no issues against your stated need for flushes. For the OP or others, go with Peggie’s authoritative opinion over mine.
Weighing 24 seasons of 20-25 nights or more on the boat and no issues against your stated need for flushes. For the OP or others, go with Peggie’s authoritative opinion over mine.
For a vented MSD potty, Peggy's chemical advice is dead on. Any of several that provide an alternative oxygen source for facilitative bacteria.
However, for a more conventional sealed potty, you are going to be better off with an antiseptic type. Yup, tested many of them, including Olorlos.
Portable head chemicals
But I would go with a desicating head instead of a porta-potty every time. Lighter, easier to service, less odor, and more capacity.
However, for a more conventional sealed potty, you are going to be better off with an antiseptic type. Yup, tested many of them, including Olorlos.
Portable head chemicals
But I would go with a desicating head instead of a porta-potty every time. Lighter, easier to service, less odor, and more capacity.
I've used some formaldehyde based garbage that stung the eyes when opened, Odorlos and West Marine ExterminOdor. The best so far has been ExterminOdor. A head filled with pure urine (no flush water, head is broken. Will replace) is currently sitting in my tank for the winter and it does not smell!
@rgranger - Is ExterminOdor the stuff that stains? I don't recall spilling it... yet
@rgranger - Is ExterminOdor the stuff that stains? I don't recall spilling it... yet
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Sorry I don’t remember the name. They came in short little white bottles that were about 4 to 5 inches tall