drill and tap holding tank

[thinwater]

Originally Posted by Eder

Wouldn't it be much easier to just add a charcoal odor filter to your vent like everyone else?

Of course, that can turn into a science project too. The "big vent" solution is best, but this is another option. In my case, I added an overflow loop to prevent plugging and over/under pressure risk. This has been in service for 7 years. I also use Oderlos or one of several similar products. Belt and suspenders.

(6 months later I replaced the clear tubing with white sanitation hose to reduce permiation and eliminate kinking. Otherwise, no problems, the carbon lasts 4 years and is easy to change.)



Sail Delmarva: Holding Tank Odors vs. Carbon Vent Filter

[Denman180]

You could put a vent filter in-line to stop the smell. Defender.com Search Results: holding tank vent filter

[captstu]

Slowly pour 1/2 gallon or more of hydrochloric acid into the head- flushing many times - and follow with a few gallons of fresh water.

The problem is not digestion in the tank, it is accumulated crap (literally) on the hoses and tank walls. this happens in fresh and salt water flushed heads, but it is many, many times more serious in salt water flushed tanks.

When you flush with HCl,open all the hatches, take a deep breath or use a scuba air source, and start with only a half cup/flush -- working your way up to a full bowl.

The overboard dump must be open when you add acid - the mixture outgases vigorously - and you must repeat until the outgassing stops.

You may have to change your joker valve at the procedure's end if the tank was especially dirty.

The smell will stop.

[Captndave1]

I have an aquarium pump attached to my holding tank, and after 3 years I have never had foul odors in my boat. Mine is 110 v and runs all the time at the dock. When out sailing, inverter continues and uses so little current that it is not a problem. Fresh is good.

[rwidman]

You can't reliably drill and tap a holding tank but you can buy this kit: https://www.westmarine.com/buy/todd-...-tanks--486613 and add whatever fitting you want.


So, you could add an additional vent pretty easily and you won't have to worry about a pump and power for it.

[S/V Alchemy]

Originally Posted by Scott Berg

Listen to Peg!!! The uniseal will work, tapping will not because the 3/8" of tank isn't thick enough (which is why they always weld bosses on where threads are

Uniseals are amazing!

Yes, if you have clearance, you could just thermoweld a desired thickness to the top of the tank and tap that. But frankly, the above solution is easier.

[Barney21]

Originally Posted by masonc

I have the usual polyethylene holding tank. I believe that the aerobic reaction necessary to break down the black water is inhibited by the lack of fresh air in the tank, resulting in stinky vent syndrome. I propose to install and aquarium pump to feed clean fresh air into the tank, in the same way sewage processing systems have aerator pumps. My problem is, the tank only has one vent. How safe would it be to drill and tap a 1/4" NTP fitting into the top of the tank? If I bedded it with 5200, would it likely be safe enough or would I be condemning the tank.

You can buy a Gland Fitting for a plastic tank. You dont need to drill and tap.
They are available at your normal plumbing supply store . You cannot tap a thread in the plastic tank alone as it is not thick enough .
You will need a bigger pump than a fish tank pump ,Idealy you will run the pump during the day when underway then turn it off at night.

[masonc]

Originally Posted by Barney21

You can buy a Gland Fitting for a plastic tank. You dont need to drill and tap.
They are available at your normal plumbing supply store . You cannot tap a thread in the plastic tank alone as it is not thick enough .
You will need a bigger pump than a fish tank pump ,Idealy you will run the pump during the day when underway then turn it off at night.

To install a gland, you need to be able to put in a backing nut.

[goat]

Cut a big hole in the top and put in an inspection plate. You can use it to back whatever you want or, ummm, inspect the tank. Bigger vent hose. My head smells of roses and unicorn farts. Beautiful.

goat (temporarily in internet range)

[peghall]

I have an aquarium pump attached to my holding tank, and after 3 years I have never had foul odors in my boat.

The holding tank, unless it's leaking, is rarely if ever the source of odors INSIDE the boat...'cuz odor from inside the tank has only one place to go: out the tank vent. A boat can smell like a swamp or even a sewer inside, and have no odor out the vent...or vice versa--be fresh as a daisy inside and gas everyone within 50 yards every time the toilet is flushed...or be odor free inside AND out the vent. So the test of your aerator isn't how odor free the INSIDE of your boat is, it's how well it's preventing odor out your tank vent.

Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
http://www.amazon.com/New-Get-Rid-Bo...dp/1892399784/

[peghall]

Sorry, Stu... There's plenty of good reason to clean out the tank and hoses, but it won't cure or prevent holding tank odor (odor out the vent) That's created when the waste in the tank breaks down anaerobically (without oxygen) even in a brand new system.

Sew Clean Sew Clean does just as good a job of cleaning out the system as HCl, and is a lot safer to use.


Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
http://www.amazon.com/New-Get-Rid-Bo...dp/1892399784/

[masonc]

Originally Posted by goat

Cut a big hole in the top and put in an inspection plate.

I think that would worry me, I would be afraid of a leak.

[masonc]

I think my best option is to remove the 1.5" inlet fitting, drill a hole for a 1/4" fitting right next to it and get a backing nut on the fitting using the 1.5" port for access.

[masonc]

Has anyone tried hot air plastic welding for PE tanks? I thought about adding a 1 x 1 inch plate for additional support.
https://www.amazon.com/Iglobalbuy-Pl...plastic+welder

[masonc]

Originally Posted by captstu

Slowly pour 1/2 gallon or more of hydrochloric acid into the head-

Please don't do this, it is dangerous and will damage your head. Hydrochloric acid is very dangerous in closed spaces and without specialized equipment.