Holding tank filter

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

All bay long

Member
Joined
Mar 31, 2022
Messages
5
Sorry gang if this has been posted before. I have a 1997 36’ Sabre express that has a sack type holding tank. It was never equipped with a carbon filter. I want to install one but would like to know if there is a particular distance from the holding tank that I should install it.
 
I don’t know if I would trust a bladder holding tank. I would be worried about it leaking. Generally holding tank vent filters are a bad thing. They inhibit air flow through the tank. Air flow is what stops the smells in a holding tank. Without air flow, actually oxygen, you get anerobic bacteria growing and that is what really stinks. Aerobic bacteria doesn’t stink, because it has oxygen. I always put in 2 large vents in my holding tank and don’t need any filters or chemicals. But I don’t know how to do that with a bladder holding tank. If it were my boat I would toss the bladder tank and get a quality plastic tank from Ronko.
 
Don't add a filter. Add a chemical such as Sodium Percarbonate each time you flush and periodically clean the tank. Adding a filter limits the flow of air in and out that inhibits the natural breakdown process (which removes the odor from your waste tank).


Ted
 
LOL made me think of these "sack type" tanks:

Glenmal 5 Gallon Bucket Portable Camping Toilet Seat Toilet Bags Camping Hiking https://a.co/d/0jg21bbh

But seriously, to the OP question, assuming it has a standard vent line and vacuum head (etc) then I expect the standard installation for a Big Orange filter or the like would be fine.
 
Thank you all for your replies. This bladder type holding tank is about 10 years old and still doing great! It does well with the layout as you can get these type of tanks into oddball places without any major dismantling of surrounding materials. I guess based off alot of the responses that it’s a bad idea to put any type of restriction inline of the vent hose so, I’ll leave well enough alone and just deal with the odor when we flush. 🤮
 
I’ll leave well enough alone and just deal with the odor when we flush.

You should be able to eliminate tank odor. Note ted's comment about Sodium Percarbonate. Or NoFlex Digestor is a pre-made product designed to promote aerobic bacteria in holding tanks. Available from places like marinesan.com, Fisheries Supply, etc. and less expensive if you buy 6 or more at a time.

-Chris
 
I agree with recommendation of Ted, Dave & others against filters. Use NoFlex or generic sodium percarbonate if desired... it does help significantly.
 
I removed our filter when I replaced all sanitation hoses, freshwater lines, new ME toilet, all fixtures, new sump, added water tank, etc. No odors and everything new.
 
Last edited:
...when I replaced all sanitation hoses...
That's a good point. Are you sure it's the vent that stinks and not the hoses themselves? While the material seems impermeable, it is permeable and the stink permeates over time. Rub a damp rag on the some of the hoses. The damp rag should smell damp, but not stink like sewer gas.

And buy a copy of The Head Mistress' book. You will be glad you did.
 
Mud Runner - i bought a 1.87 L container of charcoal, filled the pipe full and i doubt i used half of the container. so i have plenty left to change it out next season if necessary.

as to the charcoal getting wet. this is the type used in fish aqauriums so it 't get all gummy when wet. still a good idea not to get it wet.

hadn't thought about installing a second vent, but i am sure it wouldn't be that hard to do.
 
We all know that getting more air in contact with the sewage will encourage aerobic bacteria and reduce bad odor. The problem I see with a bladder tank is that the top of the tank is always in contact with the sewage. This blocks just about all air/sewage contact. Adding another vent isn’t going to increase sewage/air contact.
 
+1 to Noflex, it works great. Shop around though as prices vary wildly in my experience. Generic percarbonate is another another possibility as noted.

I assume the Sabre has fresh water flush, but just in case, if it's raw water flush, I would change that to fresh water before or along with any of the other recommendations here (agreed on the plastic tank, anything flexible makes me nervous!)
 
Mud Runner - i bought a 1.87 L container of charcoal, filled the pipe full and i doubt i used half of the container. so i have plenty left to change it out next season if necessary.

as to the charcoal getting wet. this is the type used in fish aqauriums so it 't get all gummy when wet. still a good idea not to get it wet.

hadn't thought about installing a second vent, but i am sure it wouldn't be that hard to do.
It may not be necessary if you replace the "vent" thru-hull, which is designed to keep sea water out of the fuel and water tanks so doesn't allow any air exchange, with an open bulkhead (aka "mushroom") fitting. This will allow the air exchange needed to keep the tank aerobic and has the added advantage of allowing you to prevent vent blockages by putting a hose nozzle against it to back flush the vent line every time you pump out and/or wash the boat. Anything that's tried to set up housekeeping in it will just get a water slide ride into the tank.

--Peggie
 
Back
Top Bottom