Latest Thinking on Holding Tank Additives
- Thread starter Johnb
- Start date
About 10 years ago I switched from Odorlos to Zaal Noflex Digester. I have been happy with the change. I shake about a teaspoon into the head every day and flush it through. With the Odorlos, I has having a lot of ploblems with a shale like buildup on the bottom of the tank that would break free and clog the outlet. The Noflex has solved that.
We've been using Camco TST Max (amazon link) with good results. The latest products like TST and Noflex are oxygenating chemicals. When they dissolve in the tank oxygen is released which the aerobic bacteria love.
I'm a big fan of NoFlex because it not only prevents odor out the vent, but also dissolves sludge on the bottom of the tank. Only drawback: it's expensive. I'm also a big fan of Odorlos because it promotes oxygen release from the waste itself. It doesn't dissolve sludge, but the solution to that is simple:
No matter what tank product you use, at least 2-3x/season (or every couple of months if you use your boat year round), rinse out the tank by putting 4-6" of water into it VIA THE DECK PUMPOUT FITTING 'cuz that sends the water into the tank at the bottom to stir up any sludge and hold it in suspension so it can be pumped out....Pump that out...repeat, repeat until you're pumping out clean water. If you have a macerator pump, use it to rinse out the macerator pump and its plumbing the last "repeat." This should also be done in preparation for winter or other extended layup.
BTW...Odorlos is a lot expensive from RV supply stores than marine stores.
--Peggie
No matter what tank product you use, at least 2-3x/season (or every couple of months if you use your boat year round), rinse out the tank by putting 4-6" of water into it VIA THE DECK PUMPOUT FITTING 'cuz that sends the water into the tank at the bottom to stir up any sludge and hold it in suspension so it can be pumped out....Pump that out...repeat, repeat until you're pumping out clean water. If you have a macerator pump, use it to rinse out the macerator pump and its plumbing the last "repeat." This should also be done in preparation for winter or other extended layup.
BTW...Odorlos is a lot expensive from RV supply stores than marine stores.
--Peggie
No Flex really made a difference in my system. I just removed it all for a composting toilet and the tank had little to no build up after using Noflex for two years.
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That was what I found also. I used Odorlos for about 15-years in both my boat and RV and it did a great job of keeping the tank smelling like mostly nothing. But I persistently got a buildup of a hard shale like material on the sides of the tank that no amount of flushing would remove. When it got thick enough, it would flake off in slabs about 1/4" thick and 2-4" is width which would stack up on the outlet and plug it solid. When that happed, the only way to empty the tank was to use a snake down the inspection port to break up the pieces while the pump out removed the debris. Most of the time, I would notice a partial blockage so that I could empty and flush the tank before going at it from the inside.
But there were those few times....
I have been using NoFlex for 4-5 years with no more buildup.
I switched from Odorlos to West Marine ExterminOdor. ExterminOdor has eliminated the odor for the past three winters in while the boat is in winter storage (4-6 hour journey with no option to pump out). This is the same stuff my yard is using on the boats they service
I wonder if that is the point. Let all those bubbles break up the sludge. So, would you pump in a bunch of baking soda and let it get mixed up with some vigorous sailing and then pump in the vinegar?
It would sure get interesting if you put in too much. I would suggest not standing too close to the tank vent after adding the vinegar. I remember making my tabletop volcano when I was a kid.
I
Photos might be entertaining...
--Peggie
I'd wait a while to open the pumpout cap too...and to be on the safe side, leave the lid on the toilet closed too.
Photos might be entertaining...
--Peggie
Explosion at the marina. Film at 11.