Cleaning Holding Tanks

[peghall]

I am sure the Head Mistress will show up soon to add anything that I have missed.

Yep...Good morning!

It takes hundreds of pumps to fill the tank with our Raritan PH-II manual head but we have an electric water.html" target="_blank">raw-IRJDSUNE9932123321222xxeww-water deck wash system so we can fill through one or both of the 1" vent hoses which terminate in mushroom through-hull fittings high up.

Put the water into the tank via the deck pumpout fitting which sends the water into the tank at the bottom to stir up any sludge so it can be pumped or dumped out.

Those cheesy standard screened 1/2" vent fittings are too small and you can't backflush like this with them.

You can if you knock the screen out, which you should anyway to improve air exchange with the gasses in the tank. You'll never have a vent blockage if you backflush it every time you wash the boat and/or pump out.

If you're flushing out the tank, you'll have to restart with K.O. anyway, and besides, toilets designed to use pressurized fresh water use chlorinated water from their tanks...so there's no reason not to use chlorinated fresh water flush out the tank. The water in most marinas is anything BUT clean due to run off, so I wouldn't use the washdown pump at the dock...I'd get out at least a 100 yds (or far enough away from people that might think you're dumping your tank) and then just let the water run after you start the macerator to rinse out the tank. And you really should should flush the sludge out of the bottom at least 2-3x/season and especially in preparation for any winter or other extended layup....sea water is fine and you don't need to fill the tank. Just put about 6" into the tank via the deck pumpout fitting and turn on the macerator, letting it run till you see only clean water.


--Peggie

[zboss]

I installed one of these inside my water tanks on my previous boat to assist with cleaning. We used to use them in brewing and this particular CIP is designed to work with common high output pumps used in amature brewing and also pumps that are found on boats.

I see no reason why it couldn't be used in a holding tank.

https://spikebrewing.com/products/cip-ball

[BlackHeron]

A CIP ball hooked into the raw water deck wash system would probably make short work of cleaning inside the tank. Very interesting!

[TheWindsurfer]

Originally Posted by sailorboy1

there are sludge digesters like Noflex

have you tried just using a hose to flush water down the pump out to stir up the tank and the pumping it out?

my holding tank is 19 years old and I have never cleaned it other than the water flushing

Flush down? What I suspect a jam in the tube going to the tank. Should I remove the tube from the toilet connection and put a hose in it and flush with water?

[peghall]

Most likely your problem is sea water mineral buildup in the toilet discharge line. No need to remove the hose... flush a solution of muriatic (hydrochloric if you're in the UK) acid all the way through the line, followed in 45-60 minutes by plenty of clean FRESH water. It may require more than one application if the buildup is serious enough to reduce the diameter of the discharge line enough to interfere with flushing the toilet. Future buildup can be prevented with a cupful--no more than 2 cups...of undiluted distilled white vinegar flushed all the way through the the system, also followed in about 45 minutes with clean fresh water rinse.

--Peggie
p.s. You may not have realized that you just posted to a 2-yr old thread....