Holding Tank sludge

Piers

Piers

Well-Known Member
Joined
2 Jun 2001
Messages
3,599
Location
Guernsey, Channel Islands
www.playdeau.com
Apologies for bringing this subject to the table at Christmas time....

Over time, I believe Play d'eau's holding tank has been building up a thickening depth of sludge at the bottom of the tank.

Any brilliant ideas to dissolve it thge sludge and remove it without opening the tank at all?
 
I had lumps of calcium forming in mine and having emptied the tank as much as I could do then put 10 l of hydrochloric acid in. Left it for a couple of hours and then flushed out (well offshore). The tank ended up spotless.
 
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Put a few biological washing tabs into the tank. Works as treat. Don't use the non-biological ones your SWMBO most likely uses at home.
 
This is a perennial problem where tanks are dumped rather than vacuum pumped out and rinsed at the same time (how many boats even have a dedicated rinse port) . Digesters, acids for calcium et al all work to a degree but I have found little beats a pressure washer or even high pressure hose down the pump out port and then a good fill up with clean water and pump out done regularly, prevention is always better than cure.
 
Hi Piers,

Having suffered just this problem on the last two boats I don't think there is any easy solution. I somehow doubt that Puriclean would have the "umph" to break down a heavy layer of sludge. We tried Calgon and similar, mixed with non bio washing powder with some limited success. Hydrochloric acid would probably do the trick but could have undesirable effects on other components of the system, to say nothing of the unfavourable environmental impact. Repeated rinse and pump out is probably the best solution or failing that bite the bullet, uncap the tank and get to work with a pressure washer! Happy Christmas!

Richard.
 
IDAMAY said:
I forgot to mention that we have many other Holding Tank stories most of which are entirely unsuitable for those of tender disposition. They are certainly not suitable Christmas reading on this Forum!

R.
Click to expand...

Don't be shy, toilet and holding tank posts are always some of the funniest on here! We all enjoy laughing at someone elses expense (most having been there themselves):D
 
It's usually not sludge, but a rock solid build up of scale. It will also build up on the inside of pipes and sea cocks and eventually block them. HCL. will work well but might damage other parts of the system. I use Rydlime, but it's expensive stuff. Repeated treatment with Calgon may work.
 
Calgon is a water softener , a preventative measure and not a de-scaler. So I am fairly sure it would do nothing at all for sludge.
Biological laundry liquid makes sense for attempting to dissolve sludge.
Or perhaps for something more appropriately marketed for the task look for enzyme cleaning sticks
http://www.hollandandbarrett.com/shop/product/ecozone-enzymatic-drain-cleaning-sticks-60028474
or enzyme drain cleaner liquid
http://www.johnlewis.com/ecozone-en...e2eb45&s_kwcid=404x1228217&tmad=c&tmcampid=73
I haven't needed these but may well try a preventative dose.
 
Try this product it will get rid of the sludge, cleans hoses and smells
Noflex Digestor
Alot of write ups on forums here where people can't believe it does what it advertises to do
It comes from Canada big hit in North America you can get it in the UK now
Jetvac UK Inc

http://www.jetvac.org.uk/
 
Sea Q said:
Try this product it will get rid of the sludge, cleans hoses and smells
Noflex Digestor
Alot of write ups on forums here where people can't believe it does what it advertises to do
It comes from Canada big hit in North America you can get it in the UK now
Jetvac UK Inc

http://www.jetvac.org.uk/
Click to expand...

The only thing that seems to work on that website is the testimonials page, and then it should be singular as there's only 1!
 
Try this one they have more info on their page

http://www.gemini-ltd.com/

I have been using on it my boat for 5 years in the West Coast of Canada we don't see heavy build up of scale everyone seems to talk about .
I have seen it on the duck bills of our vacuum system but nothing in tank and hoses .
Anyways the product works great for stink and sludge removal very popular here
 
A couple of times each year, when I'm filling up the fresh water tanks, I close the holding tank outlet and put several gallons of fresh water in via the pump out. Add a good slug of holding tank treatment and allow to stew for a few hours before dumping. This seems to keep things reasonably sweet.
 
Piers said:
An article I've written for MBY on Play d'eau's holding tank will be out soon in 'Our Boats' entitled 'The Sweet Smell of Success'
Click to expand...

Apologies for resurrecting an old smelly thread, but what did Piers use to de-gunk his holding tank?
Mine seems to have a layer at the bottom that has been stood fermenting for years.
 
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