Toilet bowl chalk removal with aluminium holding tank

[Fuss]

I wondered what others are using to clean and de chalk the toilet bowl without damaging the aluminium holding tank.

I know that this is not good to have an aluminium tank but its the way it is and part if the hull. All grey and black water goes into the tank and the toilets are fresh water.

[sailvayu]

Not sure about an aluminum tank I think I would want to change that, but as for your question I use white vinegar. Not sure how it would react with the aluminum though

[Seaworthy Lass]

Originally Posted by sailvayu

?.....Not sure how it would react with the aluminum though

Vinegar will eat aluminium. Try soaking a small sample in a jar for a week and see !

[sailvayu]

yeah I seem to recall something about that and agree i would check before using it

[SimonV]

Using Vinegar is the least of your worries, swap out the holding tank ASAP.

[Seaworthy Lass]

Originally Posted by SimonV

Using Vinegar is the least of your worries, swap out the holding tank ASAP.

Or start avoiding meat! A vegetarian diet gives urine a more neutral pH .

[svHyLyte]

West Marine sells a product known as "SaltAway" that can be used quite effectively to eliminate salt and build-up in the head and hoses without damage to metal parts. We keep a squeeze bottle filled with a solution of the material in each head and, once the waste in the bowl has been discharged, add some to a few squirts of fresh water in the bottom of the bowl and pump a bit into the discharge lines. With this, we have kept the two heads aboard our boat clear and functional for 10+ years without difficulty. (Routine annual maintenance, of course, but that's not difficult.) FWIW... PS: Are you sure your holding tank is aluminum? That would be very unusual but if so, I regret to say it will not last very long and in your shoes I would replace it while doing so is merely optional rather than necessary.

[Vasco]

Disconnect discharge hose, plug it. Fill bowl with whatever caustic stuff you need to clean bowl. Drain into bucket.

[SmartMove]

A pumice stone and a little bit of elbow grease works pretty well and nothing goes into the tank.

[Lagoon4us]

Totally agree with Wayne, an Aluminium holding tank unless lined is just not going to last........

[Fuss]

Originally Posted by Lagoon4us

Totally agree with Wayne, an Aluminium holding tank unless lined is just not going to last........

Thanks for all the replies.... I think I'll go with the one to block the line and pump it out after de chalking the bowl.

On the other point about the aluminium tank... Well, it's part of the hull so replacement with another material is out of the question.

But anyway.......

I can't believe that I am the only person with an aluminium boat with an integral holding tank.... Any other aluminium boat people with long term experience???

Only high grade marine aluminium that is extremely resistant to corrosion, so this cannot be compared to just any old aluminium.

[Lagoon4us]

Ok i'm 60 years old i'm an Aluminium welder with 43 years experience. I'm qualified as a shipbuilder under AMSA Accreditation Your aluminium will likely be 5083/5086# H32 plate with 6061#T6 stringers or maybe they were cut from plate as well.

That as far as the material goes is as good as it gets and you don not use it for sewage tanks end of story.

Cheers

[SimonV]

Originally Posted by Fuss

Thanks for all the replies.... I think I'll go with the one to block the line and pump it out after de chalking the bowl.

On the other point about the aluminium tank... Well, it's part of the hull so replacement with another material is out of the question.

But anyway.......

I can't believe that I am the only person with an aluminium boat with an integral holding tank.... Any other aluminium boat people with long term experience???

Only high grade marine aluminium that is extremely resistant to corrosion, so this cannot be compared to just any old aluminium.

Are you saying the tank uses the hull as part of the tank. If this is the case then it needs to be lined or a bladder fitted, the integrity of your vessel is at serious risk.

[hellosailor]

In many construction projects (boats included) some architect or engineer carefully specs things and takes into account problems like this. And then some builder decides "I can save five hundred bucks by just changing that to a...." with no idea what damage they will be doing.

I would have to ssupect that here. That the boat was designed for something else, and someone cheaped out using an unlined integral tank instead. Simon's advice to either line it or fit a bladder really hits the spot, assuming there is no lining or coating in it already.

Calcium buildup is also best prevented by thorough flushing to prevent it in the first place.

then the question is, what else did the builder compromise? Does the yard have a reputation for building in aluminum?

[David M]

Whatever you do, do not put Lye (NaOH, Sodium Hydroxide in the tank) it will rapidly dissolve the aluminum and create hydrogen in the process. A mild acid will not hurt aluminum. Very strong alkali's will.