Holding Tank Not Fully Emptying

[Rcd]

holding tank not emptying

I purchased a 30 year old liveaboard boat that had been a bit of a slip queen in Florida. Brought her up to the Chesapeake bay and rarely did we not have some sort of toilet issue the complete trip. Wouldn't pump out fully was just one of the issues. My tank pumps out from the bottom of the tank w/ external fitting etc. After finding toilet lines partially clogged, build up at the tank fittings and #1fine cracks in the pump out line I replaced all fittings, all hoses (now PVC) and new pump out line. Also forced high pressure water through the vent tube etc. Now the tank works properly with no issues and the tanks is slowly coming rather clean at the end of a pump out. If the Pump out line, vent clear etc and tank should pump out.
Good luck, stuff happens.

 

[dennismenace111]

Pun intended? "Heads up?"

 

[greatpapabear]

I have a 1990 Grand Banks 32. 25-gallon heavy duty plastic tank. When using the dock pumpout it only empties to about the 50% level. My level indicator (external) works so I know that when the dock pump stops pulling anything else out, I can put about 10 gallons of water back in before the tank is full again. Do I really have 15 gallons of semi-sludge in there? Hard to believe. A bad pickup tube inside the tank? Plastic doesn't corrode but who knows...
All thoughts and suggestions gratefully accepted.
Thanks
Oldersalt

Hi, you ask about 'sludge'. Our Fleming 55 had exactly the problem you describe almost to 50% of its capacity.

Having talked with Lee Sanitation, a UK company, I was advised to use a product which contained enzymes which loved to eat sludge for their dinner. Sounded simple and inexpensive, so I did, following the instructions to the letter.

It worked 100% so I now have full capacity back.

https://www.leesan.com/shop/dometic-sealand-clean-n-green-holding-tank-cleanser-12-sachets.aspx

Piers

 

[HeadMistress]

If your tank had been full of sludge up to 50% of it's capacity, you would not have been able to pump out at all because the pumpout hose (or internal diptube if there is one) would have been completely packed with sludge. I suspect that the real problem was a buildup of waste and animal fats that reduced the diameter of the discharge line(s) enough that what sludge was on the bottom of the tank kept getting sucked into it, creating a temporary blockage after the pumpout was able to remove about half the contents. If a guest had flushed wet wipes (which never dissolve!) they could also have been being sucked against the discharge fitting, or jammed under the pickup tube if there is one, in the tank at about time the pumpout had removed The enzyme product you used dissolved both the sludge and the buildup in the pumpout line, hopefully also allowing any wet wipes to be sucked out by the pumpout.

Let this also be a lesson that holding tanks require a bit of maintenance. Thoroughly flush out your tank 2-3 x a season and at least annually clean the tank walls with a strong solution of liquid detergent, and also use the enzyme product continuously.

What is that product btw? Wondering if it's one that's also available in the US.

--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
--------
© 2018 by Peggie Hall
Specializing in marine sanitation since 1987
Author "The NEW Get Rid of Boat Odors -
A Guide To Marine Sanitation Systems and Other Sources of Aggravation and Odor"
http://www.amazon.com/New-Get-Rid-Boat-Odors/dp/1892399784/

 

[greatpapabear]

If your tank had been full of sludge up to 50% of it's capacity, you would not have been able to pump out at all because the pumpout hose (or internal diptube if there is one) would have been completely packed with sludge. I suspect that the real problem was a buildup of waste and animal fats that reduced the diameter of the discharge line(s) enough that what sludge was on the bottom of the tank kept getting sucked into it, creating a temporary blockage after the pumpout was able to remove about half the contents. If a guest had flushed wet wipes (which never dissolve!) they could also have been being sucked against the discharge fitting, or jammed under the pickup tube if there is one, in the tank at about time the pumpout had removed The enzyme product you used dissolved both the sludge and the buildup in the pumpout line, hopefully also allowing any wet wipes to be sucked out by the pumpout.

Let this also be a lesson that holding tanks require a bit of maintenance. Thoroughly flush out your tank 2-3 x a season and at least annually clean the tank walls with a strong solution of liquid detergent, and also use the enzyme product continuously.

What is that product btw? Wondering if it's one that's also available in the US.

--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
--------
© 2018 by Peggie Hall
Specializing in marine sanitation since 1987
Author "The NEW Get Rid of Boat Odors -
A Guide To Marine Sanitation Systems and Other Sources of Aggravation and Odor"
http://www.amazon.com/New-Get-Rid-Boat-Odors/dp/1892399784/

Hi Peggie. Good to make your acquaintance and thank you for your input. Since using the enzyme we now flush the tank regularly (using the salt water pump) and it's been behaving well. We added the enzyme just before leaving the boat and going to South Africa for 3 months, giving them plenty of time to gorge themselves until all their dinner was gone.

Re the product, it's a SeaLand product, so isn't that made in the US?

 

[markpierce]

I would be willing to bet that most any boat with some age has a clogged or partially clogged vent. Either from critters building nests from the outside or from a once overfilled tank causing stuff to be forced into the vent line. Always worth a check.

Yes. Had bees die and clog one of the several fuel tanks vents which limited use of one tank.

 

[HeadMistress]

Dometic/SeaLand products are available in the US, though I'm not sure where they're actually made because they're all SeaLand's private label brand names for other products.

There is a much better product for your tank, that not only "eats" sludge but also does an excellent job of eliminating odor out the vent: No-Flex Digestor Noflex Digestor It's a Canadian product that I know is available in Australia, so I'm 90% certain it's also available in the UK. The company CEO posts here as SeaQ.

Mark's post about bees clogging his fuel tank vents reminded me that I'd neglected to mention holding tank vent maintenance in my previous reply. Even a partially blocked vent can create enough pressure to cause flushes to back up and would also interfere with pumping out and/or dumping the tank...so keeping it clear is especially important.

--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

 

[firstbase]

Dometic/SeaLand products are available in the US, though I'm not sure where they're actually made because they're all SeaLand's private label brand names for other products.

There is a much better product for your tank, that not only "eats" sludge but also does an excellent job of eliminating odor out the vent: No-Flex Digestor Noflex Digestor It's a Canadian product that I know is available in Australia, so I'm 90% certain it's also available in the UK. The company CEO posts here as SeaQ.

Mark's post about bees clogging his fuel tank vents reminded me that I'd neglected to mention holding tank vent maintenance in my previous reply. Even a partially blocked vent can create enough pressure to cause flushes to back up and would also interfere with pumping out and/or dumping the tank...so keeping it clear is especially important.

--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

Peggie, how full should the tank be for an initial Noflex treatment? Fill'r up? Empty it out? In the middle somewhere?

 

[HeadMistress]

Read the directions on the bottle for the recommended dose for your size tank...then flush down the toilet immediately after pumping out/dumping.


--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

 

[Sea Q]

Thanks Peggie

firstbase
This is on Gemini Web page https://www.gemini-ltd.com/index.php?p=product&id=715

I hope this helps
https://www.gemini-ltd.com/pdfs/Extras/T-Rec-Marine-Holding-Tanks.pdf

With a heavily sludged tank i recommend pump as much as you can.
Then addi 1 oz Noflex for every 10 gals tank size .
Then fill with water and let sit for 24 to 48 hours then pump out
Make sure the tank is properly vented !!!
Cheers
Dave

 

[Sea Q]

Dometic/SeaLand products are available in the US, though I'm not sure where they're actually made because they're all SeaLand's private label brand names for other products.

There is a much better product for your tank, that not only "eats" sludge but also does an excellent job of eliminating odor out the vent: No-Flex Digestor Noflex Digestor It's a Canadian product that I know is available in Australia, so I'm 90% certain it's also available in the UK. The company CEO posts here as SeaQ.

Mark's post about bees clogging his fuel tank vents reminded me that I'd neglected to mention holding tank vent maintenance in my previous reply. Even a partially blocked vent can create enough pressure to cause flushes to back up and would also interfere with pumping out and/or dumping the tank...so keeping it clear is especially important.

--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

Yes Noflex is available in the UK at jetvac.co/product/zaal-noflex-digestor/
also New Zealand and Fiji
Dave