A highly technical problem

MapisM

MapisM

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Ok, not really, but I thought that a title "What to use for cleaning the black water tank?" was going to sound boring - sorry... :o

The point is, I'm going to bring my old tub to her usual winter shelter on Wednesday, and it just occurred to me that she could use a good rinse to the black water tank, before staying unused for some months.
Besides, the short cruise to bring her to my yard is an opportunity to wash the tank with whatever you guys will suggest to throw into it.
But in the small island where I am based there's only a small chandler, and I couldn't find any black tank-specific stuff.
Otoh, I guess there must be some sort of "common" stuff which is more than good enough for the purpose.
Some sort of liquid soap? Bleach, or any other disinfectant? A mix of both? Or anything else? And in which proportion?
Thanks in advance for your hints!
 
Doh! I knew that there was an easy way!
Many thanks folks, another small question, just in case:
in my boat, the black tank was retrofitted, and it has been hard enough to connect it with an underwater discharge, so there's no deck fitting.
I suppose it shouldn't be a problem for any WC component, if I just throw some tablets in the toilets and flush them, right?
Thanks again.
 
Biggest problem I have with tank and pipes is the build up of scale, which eventually breaks off the inside of the hoses and blocks the diverter valve. I treated the system with Rydlime start of last year which seems to have stopped the problem, so I'll do it again every year or two. I think Saltaway is a similar product, but both are pretty expensive, and you need a fair bit of it.
 
MapisM said:
Doh! I knew that there was an easy way!
Many thanks folks, another small question, just in case:
in my boat, the black tank was retrofitted, and it has been hard enough to connect it with an underwater discharge, so there's no deck fitting.
I suppose it shouldn't be a problem for any WC component, if I just throw some tablets in the toilets and flush them, right?
Thanks again.
Click to expand...

No inspection hatch in the top of the tank?
 
Nick_H said:
Biggest problem I have with tank and pipes is the build up of scale, which eventually breaks off the inside of the hoses and blocks the diverter valve. I treated the system with Rydlime start of last year which seems to have stopped the problem, so I'll do it again every year or two. I think Saltaway is a similar product, but both are pretty expensive, and you need a fair bit of it.
Click to expand...

I've seen you massaging your black water pipes, it is a strangely disturbing sight, you weirdo... :D:D
 
MapisM said:
Doh! I knew that there was an easy way!
Many thanks folks, another small question, just in case:
in my boat, the black tank was retrofitted, and it has been hard enough to connect it with an underwater discharge, so there's no deck fitting.
I suppose it shouldn't be a problem for any WC component, if I just throw some tablets in the toilets and flush them, right?
Thanks again.
Click to expand...
I doubt there will be a problem. Actually I do not throw the d/w tablets in whole, in case they get stuck on a pipe bend or something. I crumble several d/w tablets into a 1 litre jug of warm water and pour that concentrated potion down the deck fitting. So you could pour it down the toilets and flush it.

I have no science here, other than the fact d/w tablets seem to remove any baked-on organic material from plates and pans etc, so they surely can "eat" the inside slime of a black tank. But I think you need plenty of concentration in a several-hundred litre black tank, so put plenty of d/w tablets into the thing!
 
Wouldn't some bio wash powder or wash liquid do the job ?
I have used some screen wash although suppose it might not be available on a small island.
 
Biodegradable washing powder is also often mentioned here as being effective against undesired odours from the holding tank and would probably help in cleaning as well. Easy to flush down the toilet. I use it regurarily on my boat.

Jimmy & Nick: I just hope neither of you filmed it :)
 
I've used those Mike and they seem fine, but d/w tablets are £8 or something for a box of 80, whereas those Marine Premium items are £14 for 12 :D Plus, I have real daily evidence that the d/w tablets actually work well - the power of competition in that product line means there is no possibility of snake oil
 
Mapism, I've had no problem buying black water tank disinfectant in Italian chandlers this year! You'll find the same sort of stuff in camping/caravanning shops and probably cheaper too. I make a point of always emptying the black water tank and pumping a few flushes through each heads mixed with this disinfectant before I leave the boat every time and I've never had a problem with odours or blockages. Personally I would be reluctant to use dishwasher tablets because having seen what they do to plastic glasses and cutlery handles in the dishwasher at home, I would be concerned about damaging the plastic pipe used in black water systems. Also AFAIK, odours are caused by bacteria and I'm not sure that dishwasher tablets are designed to kill bacteria. I certainly wouldn't use something as agressive as bleach
 
Deleted User said:
Mapism, I've had no problem buying black water tank disinfectant in Italian chandlers this year! You'll find the same sort of stuff in camping/caravanning shops and probably cheaper too. I make a point of always emptying the black water tank and pumping a few flushes through each heads mixed with this disinfectant before I leave the boat every time and I've never had a problem with odours or blockages. Personally I would be reluctant to use dishwasher tablets because having seen what they do to plastic glasses and cutlery handles in the dishwasher at home, I would be concerned about damaging the plastic pipe used in black water systems. Also AFAIK, odours are caused by bacteria and I'm not sure that dishwasher tablets are designed to kill bacteria. I certainly wouldn't use something as agressive as bleach
Click to expand...
on the other hand Mike, much of the interior of my dishwashers are plastics and seem perfectly ok. ( btw I use butyl not plastic for black system pipes). D/w tablets seem to work by removing everything organic from plates/ pots, rather than killing it but leaving it there
 
I always use biological wash power. Used to use the chandlers products and found it didn't really work. A dose of bio and not only are smells gone but everything stays clean.

Cheap as chips too.
 
jfm said:
on the other hand Mike, much of the interior of my dishwashers are plastics and seem perfectly ok. ( btw I use butyl not plastic for black system pipes). D/w tablets seem to work by removing everything organic from plates/ pots, rather than killing it but leaving it there
Click to expand...

In my house I have been banned from putting anything plastic in the dishwasher by the SWMBO. Maybe its the heat rather than the detergent which damages it. I did have a problem some years ago on a Broom with holding tank odours and I ended up replacing most of the existing pipework (which was sanitation quality) because it had become porous. I was told by the supplier of the replacement pipe (who I think was Lee Sanitation) that often the cause of this type of problem is the use of aggressive bleach based domestic toilet cleaners especially with pipe runs which are fairly flat and which don't drain well . Btw, for anyone who's interested, the way to check whether sanitation pipes are becoming porous is to wipe them with a piece of kitchen towel and if the towel smells, the pipes are porous
Jfm, what is the spec of your butyl pipes?
 
as an alternative to DW tablets, have a word with Oiltechnics. Their support team is excellent, and they have a range of products which major on the biological action of enzymes to clean up a whole range of sites, from the deck of aircraft carriers to garage forecourts. And their environmental credentials are very good.

http://biotechnics.co.uk/

A company which is growing like mad, and delivering excellent, sensible, products. I use them for agr purposes. No other relationship or affiliation other than a very satisfied customer.
 
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