Holding tank v portapotti !!

pcatterall

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We may soon have to consider fitting a holding tank. I was reading an article explaining the requirements and advice for New Zealand.
Interested to read the holding tank capacity for a porta loo was 1.5 Lt per person per day for 3 days and for a 'normal' sea water toilt was 8 lt per person per day for 3 days.
So my 24 Lt porta loo in the after head would be 'legal' but to use the 'sea head' in the fwd. bog I would need to fit a 100lt tank somewhere.

Are there any advantages in having a portaloo in places like Turkey? can you fit a smaller holding tank to your sea toilet if you have a portaloo?
 
I don't think you'd get away with a smaller tank because of having a Porta loo, but it's worth checking; of course this is just the sort of question which no official has ever considered, and when the point is brought to their attention will get an automatic ' No ! '

Porta Potti's are supposedly designated by the number of ' standard flushes ' so a 235 will theoretically allow 35 goes.

I think Porta Potti's will become more standard as more and more regulations come in, UK and abroad.

At least they have a good carrying handle on the waste tank for taking ashore, and a big plus is they don't require a hole in the boat with all the plumbing waiting to go wrong; can be used when the boat is dried out aground too.

I doubt if a holding tank is practical in any boat less than say 33' and for reasons of weight and space I'd suggest the porta loo is the better option, even better if you have two.
 
Are there any advantages in having a portaloo in places like Turkey? can you fit a smaller holding tank to your sea toilet if you have a portaloo?

It is not the equipment that is legal or illegal. What is illegal is discharging sewage, plus in Turkey needing to demonstrate that you have used the pumping facilities (the Blue Card system). I don't know whether emptying your portapotti complies with the requirements there.
The strategy that makes sense is to fit as large a holding tank as possible and use it as little as possible to minimise the amount of waste you hold. A 100l tank is very difficult to fit in most modest boats, but a 60l is often possible.
 
We have bought an Airhead. After looking at all the options for a 32ft boat and deciding against the holding tank option , we need all the space we can get. We decided this was the way to go !!
Not fitted yet but will be this year.
 
It is not the equipment that is legal or illegal. What is illegal is discharging sewage, plus in Turkey needing to demonstrate that you have used the pumping facilities (the Blue Card system). I don't know whether emptying your portapotti complies with the requirements there.
The strategy that makes sense is to fit as large a holding tank as possible and use it as little as possible to minimise the amount of waste you hold. A 100l tank is very difficult to fit in most modest boats, but a 60l is often possible.

Thanks guys, I will search for the regs especially Turkey. ( I had understood that you had to have a tank suitable for the number of berths for a set number of days) Our current system when near shore is to piddle using the sea toilet and use the porta loo for number 2s ( the user has the job of emptying the porta loo so they mostly manage that while on shore!!) I suppose we could fit a small holding tank and try to just use it for piddle jobies?
Question: is it an offence to pee in a marina ( inthe water I mean!)?

Just looked at the Airhead specs, looks very useful to me and I guess we can spare the 0.06amps to run one. But would it be acceptable in Turkey?
 
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Fitted a Porta Pottie 4 years ago and never regretted it , filled the holes in the boat and no pumps to repair on a regular basis . We have not had a problem with unwanted smells and in the evening before bedding down i sometime put it in the cockpit for tho,s midnight sorti's , as its normal daytime position is next to the v berth. I know this doesn't help with you Reg's in Turkey , but i think it is a good addition to my boat .
Cheers Taunto
PS water temp here today is 20 deg C what is it in Turkey.
 
I have a Porta Pottie ... It fills the requirements, but it is a pain to empty : the official shore pumping units are too large and I don't really like to empty it in the public toilets ... but no choice unless we take a trip to sea.

Where does Sydney discharge it's sewage? ..... in the sea, and not very far off the coast. The rules are nonsense, but non-compliance could be expensive.
 
quote "Where does Sydney discharge it's sewage? ..... in the sea, and not very far off the coast. The rules are nonsense, but non-compliance could be expensive. "

True but I understand that this ( common ) practice discharges treated sewage?
 
I had a 'wrap around' holding tank on a RM69 toilet. Its capacity was 25 litres but with a diverter valve incorporated so that liquid offerings could go directly overboard. We could manage for three days without the need to pump it out. I replaced that with a 50 litre tank on a different toilet but without a diverter valve. This also gives us about three days (two people).

I have my doubts, based on all the information provided by the CA, that Turkey would accept a Porta Potti. It seems that they mostly accept an effort to comply with the pump-out regulations but turn a blind eye to the aspects of it that are very difficult to comply with, such as grey water tanks. However, purchase of a Blue Card seems to be compulsory.

I have to say that the 'holes in the boat' and extensive failures is not our experience. Seacocks and hoses are a long way down our list of things that go wrong. I cleaned out the tank last season after five years or so, not an unpleasant job after a good flush through. Blakes seacocks are highly reliable, often untouched for two seasons other than occasional operation to keep them free.
 
The problem with a Porta Potti or similar is that the chemicals used in them to neutralise smell are not wanted in most sewage systems, so a lot of places either prohibit emptying them into toilets, or would do so if they thought about it.
 
We may soon have to consider fitting a holding tank. I was reading an article explaining the requirements and advice for New Zealand.
Interested to read the holding tank capacity for a porta loo was 1.5 Lt per person per day for 3 days and for a 'normal' sea water toilt was 8 lt per person per day for 3 days.
So my 24 Lt porta loo in the after head would be 'legal' but to use the 'sea head' in the fwd. bog I would need to fit a 100lt tank somewhere.

Are there any advantages in having a portaloo in places like Turkey? can you fit a smaller holding tank to your sea toilet if you have a portaloo?

I know a boat with a Portapoti in place of the original Blake that is plumbed into the same system but it is not obvious. It works like a holding-tank in the marina and is pumped out at sea. Of course there's always the good old "bucket & chuckit"
 
I had a 'wrap around' holding tank on a RM69 toilet. Its capacity was 25 litres but with a diverter valve incorporated so that liquid offerings could go directly overboard.

I've thought about getting one of these. I understand that the diverter valves have (had?) a reputation for weakness, but otherwise it's a neat solution.
 
I've thought about getting one of these. I understand that the diverter valves have (had?) a reputation for weakness, but otherwise it's a neat solution.

We had endless problems with the diverter valve. It is a rubber disc that distorts after a while, losing its sealing capability. Also the tank is pumped out using the toilet pump, hard work, you cannot tell when the tank is empty and the pump is not the greatest.
 
quote "Where does Sydney discharge it's sewage? ..... in the sea, and not very far off the coast. The rules are nonsense, but non-compliance could be expensive. "

True but I understand that this ( common ) practice discharges treated sewage?

According to the locals the sewage system or treatment plant are at times overwhelmed by rain water and raw sewage is sent directly into the sea.
 
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The problem with a Porta Potti or similar is that the chemicals used in them to neutralise smell are not wanted in most sewage systems, so a lot of places either prohibit emptying them into toilets, or would do so if they thought about it.

The chemicals I use in the portable toilet are also used in holding tanks ..... Thetford Aqua-Kem ... label says:
THE most powerful odor control
Liquefies waste FAST!
Breaks down tissue
Powerful detergents to keep tanks clean
Active ingredient is 100% biodegradable

But right on the bottom of the label :
DANGER POISON : MAY BE FATAL OR CAUSE BLINDNESS IF SWALLOWED. A STRONG SENSITIZER-CAUSES SEVERE BURNS. VAPOR HARMFUL.

It actually contains Methyl Alcohol and Formaldehyde!

It would be more eco-friendly to use a bucket and chuck-it for sure ...... hell my **** is certainly biodegradable and is no more an environmental problem than all the other animals defecating in the water.
Frankly the laws are ridicules for any area that has a regular change of water.
 
We had endless problems with the diverter valve. It is a rubber disc that distorts after a while, losing its sealing capability. Also the tank is pumped out using the toilet pump, hard work, you cannot tell when the tank is empty and the pump is not the greatest.

I looked at the exploded diagram (not something you want to think about too literally with a holding tank) and it looked as if it should be possible to beef that valve up. Rather a lot of work, though. RM do seem to have a cheap and nasty approach to accessories - I am assured that their "wooden" toilet seats are actually MDF and last two seasons only if you're lucky.
 
The chemicals I use in the portable toilet are also used in holding tanks .....

For what it's worth, septic tanks are far more tolerant of nasty stuff than most people think. A really big dose of bleach, for example, may kill off most of the useful bacteria, but tests have shown that they re-establish themselves in a matter of hours.
 
I looked at the exploded diagram (not something you want to think about too literally with a holding tank) and it looked as if it should be possible to beef that valve up. Rather a lot of work, though. RM do seem to have a cheap and nasty approach to accessories - I am assured that their "wooden" toilet seats are actually MDF and last two seasons only if you're lucky.

The diverter valve for the RM69 holding tank is a simple spectacle blind with an O-ring in a groove on the sealing face. Sliding the plate across tends to dislodge the O-ring, upon which the diverter valve doesn't seal and water leaks past. It's a major task to dismantle the valve, a dozen or so nuts and bolts and fiddly seals.

The rotating check valve in the pipe to the tank is the one with the rubber seal that distorts. When we had ours this part was not even shown on the parts diagram and no spares were listed. We had to contact the company direct to get one.

Shortly after buying our toilet in Holland we saw a beautiful teak seat and lid for one at a local chandlery. It cost a packet but we bought it anyway as it was so nice to use.
 
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