SOG... Whats the verdict...???
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Re: SOG... Whats the verdict...???
I tried the napisan San treatment for a couple of years and gave it away as a bad joke. Firstly I tried it because I was told it was a cheaper way to go. Well that was crap. Secondly because the dose was easy. Well more crap as the amount use can be effected by different variables. Ambient temp, each number 2 etc. If emptying a cassette every 2 or 3 days then it may not be an issue but as I have a black tank it is a couple of weeks between emptying. I started using the heavy duty bio magic which is recommended for black tanks and found the results were great. Sure it's about 100 bucks for 5 ltrs but it lasts over 12 months, so about the same if using napisan.
Full time on the road in an Alpine 2855
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Re: SOG... Whats the verdict...???
Hi all
Someone already mentioned it but SOG is a completely different technology that a fan that sucks the smelly air out from the “airgap” of a tank. It is the active agitation of the medium to introduce dissolved oxygen so that aerobic bacteria (the less smelly type) can actively breakdown the biomass and overpower the anaerobic bacteria (the smelly type). So understand that a MH or caravan SOG essentially sucks the gasses from the “airgap” in the tank on top of the medium. This means that any gasses in the tank are less likely to escape into the cabin when the toilet is flushed. It has very little or no effect on the actual bacteria present in the medium. Dissolved oxygen levels determines which of the two bacteria becomes dominant.
I have no ties to them but a business called Biomagic is run by a lady called Jackie and she is brilliant at this stuff. She has s masters in thisxstuff and last time I was talking to her it looked like she was going to do a PhD in environmental impacts of industry in a wilderness area.
Anyway, hope this helps.
Mick
Someone already mentioned it but SOG is a completely different technology that a fan that sucks the smelly air out from the “airgap” of a tank. It is the active agitation of the medium to introduce dissolved oxygen so that aerobic bacteria (the less smelly type) can actively breakdown the biomass and overpower the anaerobic bacteria (the smelly type). So understand that a MH or caravan SOG essentially sucks the gasses from the “airgap” in the tank on top of the medium. This means that any gasses in the tank are less likely to escape into the cabin when the toilet is flushed. It has very little or no effect on the actual bacteria present in the medium. Dissolved oxygen levels determines which of the two bacteria becomes dominant.
I have no ties to them but a business called Biomagic is run by a lady called Jackie and she is brilliant at this stuff. She has s masters in thisxstuff and last time I was talking to her it looked like she was going to do a PhD in environmental impacts of industry in a wilderness area.
Anyway, hope this helps.
Mick
Mick and Trace living the good life!
Winnebago Alpine 2007
Winnebago Alpine 2007
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Re: SOG... Whats the verdict...???
I installed a SOG unit to the cassette enclosure lid when I fitted out the Oka in 2011, has worked well ever since with a yearly replacement of the charcoal filter. The cassette has never had any chemicals in it full stop, just poop and wee.
One thing to note though is that if the cassette is over half full and you are doing any windy roads or four wheel driving than it is best to disconnect the hose and fit the plug to the lid, not a good look with the contents running down the side of the truck and the little fan and the carbon filter don't like it either!
If I was doing the install again I would run the vent to the roof level but that is a bit hard in our situation as we have a poptop roof which is the same size as the truck body, it would also avoid the fumes under the awning
)
One thing to note though is that if the cassette is over half full and you are doing any windy roads or four wheel driving than it is best to disconnect the hose and fit the plug to the lid, not a good look with the contents running down the side of the truck and the little fan and the carbon filter don't like it either!
If I was doing the install again I would run the vent to the roof level but that is a bit hard in our situation as we have a poptop roof which is the same size as the truck body, it would also avoid the fumes under the awning

Oka 4WD camper/motorhome, 1100w solar, 400ah lithium, diesel heating, HWS and cooking
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Re: SOG... Whats the verdict...???
Hi Mick,
There are three types of bacteria that help break down the waste, aerobic, anaerobic and facultative. Aerobic can not live in the same environment as anaerobic. One lives in an oxygen absent environment and the other lives in an oxygenated environment. Facultative can live in either environment and with either aerobic or anaerobic bacteria.
Regardless of how they work a SOG system in a cassette that requires emptying every 2 to 3 days doesn't really have time to break down the waste. The SOG system is nothing more than an extraction fan. True SOG systems will have the air entering from the bottom of the tank into the effluent, thus increasing oxygen levels in the effluent. This is how a real sog system works. If all you want to do is prevent smells entering the RV then this system will do that but does little more.
There are three types of bacteria that help break down the waste, aerobic, anaerobic and facultative. Aerobic can not live in the same environment as anaerobic. One lives in an oxygen absent environment and the other lives in an oxygenated environment. Facultative can live in either environment and with either aerobic or anaerobic bacteria.
Regardless of how they work a SOG system in a cassette that requires emptying every 2 to 3 days doesn't really have time to break down the waste. The SOG system is nothing more than an extraction fan. True SOG systems will have the air entering from the bottom of the tank into the effluent, thus increasing oxygen levels in the effluent. This is how a real sog system works. If all you want to do is prevent smells entering the RV then this system will do that but does little more.
Full time on the road in an Alpine 2855
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Re: SOG... Whats the verdict...???
In my 12 years experience over three vehicles with the SOG I can vouch for the fact that they are a convenient and cheap way to ensure that no smells enter or remain inside the van/motorhome. In support of what Craig and others have argued, you cannot drink the resulting fluid.
I have never experienced overflow through the vent hose but that would, I imagine, be a consequence of the positioning of the exhaust tube in relation to the tank outlet.
I have never experienced overflow through the vent hose but that would, I imagine, be a consequence of the positioning of the exhaust tube in relation to the tank outlet.
Steve Williams
http://stevew1945blog.com/
Every absurdity has a champion to defend it.
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http://stevew1945blog.com/
Every absurdity has a champion to defend it.
Oliver Goldsmith. 1728 -1774
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Re: SOG... Whats the verdict...???
If the vent was out through the roof, would the fan unit be at the cassette end or on the roof end? Does the fan blow air into the cassette or suck it out?
A person may fail many times, they only become a failure when they blame someone else John Burrows
Those who struggle to become a leader, rarely know a clear direction forward for anyone but themselves
Those who struggle to become a leader, rarely know a clear direction forward for anyone but themselves
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Re: SOG... Whats the verdict...???
Push or pull fan ...??? is there a difference , the suck fan would suck to be a suck fan, suckin all the stench past it, rather be the push fresh air fan thats for sure...
vik...
vik...

Merk 4x4 VF30 519 CDI 2020 LWB V6TD 3 ltr 6 wheeler ,Tenorite Grey ... yep, it's not white ...!!! 

Re: SOG... Whats the verdict...???
Our 'home' toilet is essentially a SOG design & works perfectly. Has had around a years use now. Urine & solids go to different places. Mixing the two together always makes things smellier.
Has a 'suck' fan.
http://www.abetterwaytogo.com.au/separett-villa
Has a 'suck' fan.
http://www.abetterwaytogo.com.au/separett-villa
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Re: SOG... Whats the verdict...???
Sounds more like how a composting toilet works Cuppa.
Full time on the road in an Alpine 2855
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Re: SOG... Whats the verdict...???
The SOG that we owned never let solids or liquids back into the tube ,even after a rough ride ,but it did
keep the smells out.
keep the smells out.
Billie Blue