What’s the best toilet brush for a boat?

Don't have any metal bits on brush or holder - they rust! Also, if you want a holder, make sure it can't topple over, spilling anything that has collected inside.
 
I have a neat little brush and holder that fits on the bulkhead. I have no idea what brand it is or even where I got it, but it is quite small and vaguely rectangular in section, maybe three inches deep. All. Can suggest is keep looking because they do exist.
 
Without a shadow of a doubt, this one:

OceanAir Brush & Stow Toilet Brush

Beautifully designed, brush head perfect snug fit it Jabsco toilet ‘throat’. Well sealed when brush put back in container so I leave some bleach in there to keep things ‘pleasant’. One of the best things I’ve ever bought for the boat - admittedly I’m quite fastidious about a clean heads though!

Agreed - we had one on our last boat. Silly price, but does the job perfectly.
 
If...

you can find a conventional old fashioned loo brush with. black bristles...

you can hacksaw the head down to a suitable size for the bowl.
 
after extensive experimentation, a "zero brush" approach has been adopted. Pump a few times to remove most of the faeces, then clean any residual skid marks with paper which is then flushed away. All brushes will retain some faecal material (unless treated with bleach or other stuff) which is too likely to pose a health hazard on board.

You can wash your hands very well after said process.
 
after extensive experimentation, a "zero brush" approach has been adopted. Pump a few times to remove most of the faeces, then clean any residual skid marks with paper which is then flushed away. All brushes will retain some faecal material (unless treated with bleach or other stuff) which is too likely to pose a health hazard on board.

You can wash your hands very well after said process.
That’s one idea (although I’d be interested to see the ‘extensive experimentation’ report. What control was used? How was effectiveness measured?)

One thing that’s putting me off is that it would add excessively to the already lengthy briefing for guests regarding the use of the heads (and general safety) on board. I think I’ll draw the line at demonstrating how to push one’s fingers down the narrow throat of the Jabsco to thoroughly clean the offending area.

I suppose one difference between cleaning in your described way and eating doughnuts is that after both you wash your hands but after one you have a choice of licking your fingers first.
 
I keep a 1/2 litre bottle of cheap washing-up liquid on the shelf, and squirt a bit in the bowl, where the brown trout are likely to hit the runway. It prevents any 'matter' sticking to the porcelain, and it all slips down the hole like an oyster.
I don't use a bog brush, and assume that crew have the decency to leave everything clean and proper by wiping with a piece of bog paper.
 
... clean any residual skid marks with paper which is then flushed away.
Flushed where? I hope you mean you flush it into your black water tank. Or are you just polluting your anchorage?
I have a zero paper policy. Only human waste flushed, into holding tank where appropriate.
Any paper or other sanitary products go into a bag in a sealed box (also IKEA).
This is partly because there is nothing worse than swimming through toilet paper and partly because I don't want to unclog the plumbing when a novice crew dumps an entire roll into the bowl and expects it to be flushable.
I am also particularly averse to "wet wipes" being flushed as these will not degrade and add to further plastic pollution in the ocean.
I do realise my approach passes the buck on to local authorities to deal with my waste, but (at least here in Italy) I pay for this privilege.
 
Flushed where? I hope you mean you flush it into your black water tank. Or are you just polluting your anchorage?
I have a zero paper policy. Only human waste flushed, into holding tank where appropriate.
Any paper or other sanitary products go into a bag in a sealed box (also IKEA).
This is partly because there is nothing worse than swimming through toilet paper and partly because I don't want to unclog the plumbing when a novice crew dumps an entire roll into the bowl and expects it to be flushable.
I am also particularly averse to "wet wipes" being flushed as these will not degrade and add to further plastic pollution in the ocean.
I do realise my approach passes the buck on to local authorities to deal with my waste, but (at least here in Italy) I pay for this privilege.
No wet wipes. Agreed. I am in the same waters as JM... tidal...
 
Studying the description, I think it cannot get high up the bowl under the flush rim. The charter boat I have just vacated could have done with a different design of brush that was capable of that...
Beg to differ, they do?
 
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