holding tank filter

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tomsboat

Senior Member
Joined
Aug 18, 2015
Messages
113
Location
Bronxville
Vessel Make
Mainship Trawler
I received a bill for replacing my holding tank filter for winterizing my boat.The filter cost was $95.61.I have a 2007 40ft mainship trawler can anyone tell me where this filter is?I never had a bill on a holding tank filter I don't know if I have one.Tom
 
Wherever it is located, I would get rid of it. Holding tanks need a lot of air so they do not go anerobic. Peggy Hall is the guru on holding tanks and everything related. She is very much against filters since they block air flow. If you get adequate air flow in and out of the tank you will not need a filter to get rid of the smell because there won’t be any smell.
 
Just curious, what the F does a holding tank filter, filter? In 60 years on the water and in yards I've never seen or heard of one. No point in filtering the air, and not reasonable on the poop side. I've only owned holding tanks on ships and there was no filter. And no I don't put sewage in the water.

But at $100 a pop, it might be a good specialty to get into.
 
A holding tank 'vent' filter would be between the tank and the vent opening. Trace the vent line to find it.
And it does "filter" the smell. It's usually filled with activated charcoal or something.
 
On my Mainship the holding tank filter was located atop the holding tank and connected to the vent line. I got rid of it as per the advice of the previous post.
 
If you’ve ever had a party on your aft deck on a calm day and one of the party flushes into a half full holding tank you will find out Exactly what these filters do. I had a client who wanted to sell his $750k cruiser because she smelled so bad.
$80 for a West Marine holding tank vent filter and it’s still good. Very easy to replace every two years.
Worth every penny!
 
I received a bill for replacing my holding tank filter for winterizing my boat.The filter cost was $95.61.I have a 2007 40ft mainship trawler can anyone tell me where this filter is?I never had a bill on a holding tank filter I don't know if I have one.Tom

Any filter would be installed in the holding tank vent line. It traps odor out the vent when the toilet is flushed. It also helps to create the odor it's sold to eliminate. If the yard is charging you to replace a filter, ask them to show you the work order specifying replacement and show you the one they replaced. I suspect there was one 'cuz if there weren't, they'd have had to cut the vent line to install one...and it's unlikely they'd have done that without a work order from you.

If you have no idea where any holding tank filter would be or whether you had one, it's pretty strong indication that you've never seen any of your sanitation system plumbing...'cuz if you had, I'm pretty sure you'd have found it wondered what the heck it was. That's also a strong indication you're unaware that, unlike household toilets, marine toilets, holding tanks--and yes, vent lines!--are working working components in a system that requires preventive maintenance unless you want to spend a lot of time and/or money on repairs. So I'm gonna suggest that you check out the link in my signature (just click on the title). The title (my publisher's idea) is a bit misleading...'cuz although it does deal with every source of odor on a boat and how to cure, or better yet PREVENT 'em, it's actually a comprehensive "marine toilets and sanitation systems 101" manual that explains the laws, describes all the types of systems and how they work, and will help you learn how to operate and maintain your system to prevent 99% of problems instead of having to cure 'em. 'Cuz you get to do any preventive maintenance on your terms when it's convenient...the need to cure a problem never happens when it is! And I'm always glad to answer any questions it doesn't.

Any btw, it also includes complete instructions for winterizing your own plumbing--fresh water as well as sanitation systems.

----Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
 
I received a bill for replacing my holding tank filter for winterizing my boat.The filter cost was $95.61.I have a 2007 40ft mainship trawler can anyone tell me where this filter is?I never had a bill on a holding tank filter I don't know if I have one.Tom


As others stated, if you have one it will be in the vent line. And yes, they are pricey, I once checked a replacement for my boat (located between the hull and the inside finished wall) and it was in the $95 range. There are two very different thoughts pertaining to stink filters (carbon of course), one group believes the solution is to prevent it from ever occurring it the holding tank.

The other is to not concern one's self if there is stink in the tank, just filter it in the vent line. And uncontrolled stink will knock your socks off every time there is a disturbance that adds to the tank's contents such as flushing a head.

No preaching, the choice is yours as to which method you prefer. I decided to stick with a carbon filter. There is an ad frequently seen on TV, "no pinch, no stink, no worry!'' Whoops.... that was for something else :flowers:
 
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The ends of the vent filter have male hose threads. My previous boat had the filter installed. I removed it and cut a piece of PCV pipe the same length and glued on hose ends and screwed it in place of the filter. Solved.
 
Yep if you buy them online or at WM they are around $100 or more.

BUT!!!! Here is an easy way to make your own for less than $10-15.....

http://www.boatinghowto.com/content/building-holding-tank-filter-288/

Yes - we made one of these in a similar fashion but a bit larger for a few boats and they worked great. Filled with active charcoal for aquariums that you can get at Walmart for about $5 a quart container.
Works great and easy to change media when needed.
 
I never thought of Wally World for activated charcoal! That is worth considering. Rather than replacing my water filter when stink starts I might just chuck it and fill the filter container with $5 of charcoal from Wally.
 
My 390 has one. I change it every season. Mine is a Voker. Costs about $50.00 for the replacement. Works great and eliminates that foul smell on that calm day.

Peter
Schatzi
2000 390 twin
 
Our vent filters last 4-5 seasons, and we're on the boat a lot...

-Chris
 
Our 390 had one when we bought the boat. After the first season the boat had a terrible smell inside and out. I found the filter and removed it. Have never had a smell issue since. The 390 has a bottom discharge for the macerator. If the valve is left open the holding tank will quickly fill with seawater. If water goes from the tank into the vent it will soak the filter, clogging it. I believe that is what happened to me.
John
 
...And the thru-hull should always be kept closed except when dumping the tank.
Because it doesn't take a siphon to fill the tank. Water will always rise through an open thru-hull to the waterline, and will fill any part of the tank that's below the waterline, even when the boat is at rest.




--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
 
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This is the best $90 bucks you'll ever spend, especially if your wife has ever caught a whif of a holding tank BURP!
 
Are any of the filter companies publically traded? I want in on some of this!
 

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