cleaning head tanks

[nomadic star]

Hi we are pretty new to sailing and have just bought our first boat. just wondering how do you flush holding tanks out ? would appreciate advice please.

[Nigel]

just wondering how do you flush holding tanks out ? would appreciate advice please.

I guess it depends how clean you want to get them! Just filling and emptying a couple of times gets most debris out, but adding: bleach, hydrochloric acid, caustic soda, WC cleaner, or dishwasher tablets are all possibilities.

Note: do not add any of these at the same time. 

[Moodymike]

You can get cleaner from caravan dealers

[vikinglish]

We put "loo blue" with some water into the near empty tank when we leave the boat for a while to prevent it solidifying. Does a great job. Periodic cleaning with a few litres of undiluted coca cola is reckoned to be agreat way of giving it a good clean. Keep meaning to try it.  Most important thing ive learnt after too many blockages is that loo paper is a no no. Doggy bags now hang from the heads. Visitors screw their face up on first visit but dont seem to mind it so much when i tell them that he blocks it unblocks it!

[Ian 2010 B32]

I think this was a more basic question: HOW do I fill the header tank with fresh water to rinse it, rather than what to add to that water. (Although those are all good tips.)

I'm also looking at my new (to me) 2010 32 with the same question. Do you open the flushing cap beside the tank, on the outside of the boat, and fill it with a hose before emptying it through the sea cock? Or does that outlet have a one way valve to prevent waste and water flowing back into the tank from the outside? Can you fill it from the sea cock? Pump it via the bowl (definitely can, but that's the hard way compared to a hose in the hole!)

[MIA]

I filled by using a hose from the waste outlet on the deck, but it will not completely fill the tank, due to hydrostatic pressure, so once the water overflows on the deck then use the pump on the toilet to completely fill the tank, mind and keep the seacock closed, the water will come out the breather when tank is full. I put some blue loo cleaner in with it when flushing

Stevie

[njsail]

I used to fill the holding tank from the discharge outlet on the deck with fresh water over and over then flush a lot of fresh water through the head as well.    Last year when I changed out all the thru-hulls, sea cocks and all the head plumbing I had to also remove the holding tank.  I took the opportunity to really flush out the tank and give it a proper clean out.  It was in great condition (love poly tanks) and a messy job but the result should help a while.  We had an awful stench in the head and after changing out the hoses everything was fine.  Doesn't smell like a rose garden but its not bad either.   

I wanted to post a couple pics of the holding tank out.  There is an access port on top that on the Bavaria 40 Ocean you can't see because it's just higher than the shower wall when installed.  This plate comes out for full access to the inside of the tank and certainly makes a full cleaning much easier.   Every time we pump out I also dump a bunch of fresh water into the tank and empty it again just trying to help clean out anything remaining at the bottom of the tank.   Good luck in your quest to clean the tank out.   

[Moodymike]

On the second pic (the base).  I presume one is the pump outlet , why is there no hose tail?

[njsail]

you're very observant.  Ironically the tail pipe was only screwed being held in by a couple threads.  That wouldn't have been fun had that fell off.  It was easier to take it off for cleaning and then re-seat it.   Bavaria makes it easy to access everything needed to do the job.   On a lot of other boats it's a major project.  This is another reason why disassembling your boat little by little is a good thing.  If I didn't go the extra step and remove the holding tank I might never have noticed the tail pipe wasn't fully assembled correctly.  In any case now it's all new including the head and all is well.  Now travelling with a boat full of women is a little easier.   /quick mini rant:  When I was replacing all the thru-hulls and sea cocks on the entire boat I had to wonder why anyone would use steel handles on a marine sea cock.  It just doesn't make sense.  I felt they were starting to rust through and might become a safety issue and decided to do the job right.  /quick rant off.