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quoteKeeping things clean is the key to success with the toilet in your leisure vehicle. And that starts with whatever way you want to break down waste.
More than ever, there are alternatives to potentially harmful – yet usually highly effective – chemicals. The effect has to be the same, of course – stopping bacteria, breaking down toilet waste so that the contents of any holding tanks (often called cassettes) can be disposed of safely, reducing gas build-ups and keeping unwanted smalls under control.
Flush with success
It’s worth noting an increasing number of campsites are demanding the use of more environmentally friendly toilet cassette chemicals. Always check before you book/arrive on site.
Here, we’ve covered off the main cassette toilet chemicals, but don’t forget there are also plenty of other cleaning, lubricating and maintenance fluids.
How do we stop our motorhome or caravan toilet smelling?
It’s one of the biggest unspeakables in the world of leisure vehicles, but toilets can get a bit whiffy.
There are lots of products out there that will help – roughly divided between those that add a more pleasant smell and those that neutralise bad smells. It’s up to you to find the one that suits you best. Generally, though, a proper cleaning regime using products designed specifically for leisure vehicle use will overcome any difficulties.
Environmental impact?
In the past, most toilet cassette cleaning fluids relied on formaldehyde as the most effective chemical for breaking down toilet waste. Today, there are plenty of “greener” alternatives that are just as effective. In fact, a typical caravan or motorhome cassette toilet is far more friendly to the environment than what you have at home, including using significantly less water.
As Thetford puts it: “A typical four-person household flushes the toilet five times daily at home, using a significant amount of water. The water consumption drops spectacularly when they switch to Thetford’s portable sanitation solutions during a three-day campsite holiday. Due to the minimal flush water usage, only 17.5 litres of water is wasted, a mere 5% of the water used at home.”
Top caravan or motorhome toilet cassette tips
- Keep any eye out for what toilet cassette chemicals are allowed at any campsite you’re intending to visit. Expectations do vary from site to site.
- As you can probably guess, some products are far safer if children and/or pets are around.
- Try and keep toilet paper usage to a minimum. Cheaper two-ply paper will dissolve quicker than more expensive multi-ply variants, but all this is often down to individual preference and experience.
- Generally, it’s advised not to travel with your toilet cassette over half full. Pressure in the holding tank will vary depending on altitude and temperature, so err on the side of safety. Excess weight sloshing around is not great for vehicle economy or even handling.
- Also, in extremely cold weather, it’s just possible that the contents of your toilet holding tank will freeze (it can happen whilst you’re travelling, even). Check manufacturer advice for adding an anti-freeze type product, or just drain down fully if appropriate.
- Do not use normal domestic cleaning products, especially bleach, in your leisure vehicle toilet. It might damage rubber seals as well as any plastics. Seals and moving blades should, however, be lubricated with specialist products; alternatively, a smear of olive oil.
- If you’re switching between using products containing formaldehyde and those that are formaldehyde-free, clean the toilet cassette and its holding tank with a proprietary product that will kill any formaldehyde residue which may otherwise prevent any other treatment from working properly.
- Most of the products mentioned below can be used on plumbed-in cassette toilets as well as camping-style portable toilets, but do always check.
- Check out manufacturers’ and leading retailers’ websites for “how-to” videos and more.
- Look out for special offers (bulk purchases etc) if you want to make long-term savings. But don’t over-buy.
See also…
Our guide to using your motorhome or caravan toilet here: www.caravanguard.co.uk/news/the-great-taboo-using-your-motorhome-or-caravan-toilet-23490/.
Let’s look at a selection of motorhome and caravan toilet cassette chemicals…
Star Player #1
Thetford Aqua Kem Green concentrated toilet fluid
A concentrated toilet fluid in a 750ml plastic bottle that’s actually the equivalent of two litres of standard Aqua Kem Green and can last for up to 40 days, according to Thetford. That’s based on an ideal dose of 75ml for every one to three litres of water (it depends on temperature), with each dose lasting up to four days.
Marked Green because it’s the environmentally-friendlier version of the Blue equivalent, it liquifies waste and reduces any gas build-up. It will also protect the whole toilet.
Key features Concentration means space and weight savings, odour control
Expect to pay £12.95
Star Player #2
Thetford Aqua Kem PowerPods Bio
Typically retailing at £5 more than the Blue equivalent, these offer the same cleaning and odour control properties as the above, albeit in pod form – meaning you get your dosage right every time. They also come in packaging that, for many, is more convenient, saving both space and weight (total weight is 0.89kg compared to similar weight for Aqua Kem Green, but PowerPods offer double the usage. Each pod will last up to four days.)
Simply place a pod directly into your toilet cassette and add a suitable amount of fresh, cold water – normally, between two and three litres.
Key features Resealable pouch, 20 pods in each, non-pathogenic micro-organism technology, easier to handle than fluids in bottles
Expect to pay £25
Star Player #3
Solbio Natural Caravan Toilet Fluid
A 100% organic toilet fluid that offers four-in-one action. Use it as you would any typical toilet cassette fluid. It will naturally break down toilet waste and neutralise any smells (rather than just covering them up). It self-cleans and sanitises the toilet. It can also be added directly to the toilet cassette to help break down toilet paper.
Solbio can also be added to your waste water tank to prevent any build-up of algae or deposits.
The 1.6-litre size offers up to 40 doses. The manufacturer advises you should replace the fluid dose every three to four days.
Key features Chemical-free, biodegrades waste and toilet paper, prevents smells, Eco- and vegan-certified, pine and eucalyptus fragrance
Expect to pay £24 (1.6 litres)
Star Player #4
SOG Type B Door Model
A totally chemical-free way of processing your toilet waste, which doesn’t even rely on specialist toilet paper. Instead, an electric fan is the key part of a small kit that’s easy to fit alongside your toilet system.
From Germany, SOG makes environmentally-friendly kits like this to suit most cassette toilet systems from Thetford and Dometic.
This is the most straightforward model and comes in a number of variants. The Type B here is for Thetford C200 cassette toilets (you’ll need to check which suits yours).
The fan is mounted directly on the inside of the disposal flap, while the housing, which attaches to the door of your cassette locker, is a housing for an activated carbon filter.
The automatic operation of the fan each time the blade separating the toilet bowl and holding tank is opened means more oxygen flow, in turn optimising waste breakdown – with gases neutralised via the carbon filter, meaning no odours. Also, you’ll need to empty your cassette less often because all waste is decomposed more.
Because there are no chemicals involved, it means you can empty your toilet cassette anywhere that takes domestic sewage. It also allows the use of normal domestic toilet paper.
The plastic housing itself is available in a choice of colours and/or can also be painted.
Key features Totally chemical-/liquid-free, organic carbon filter mat, low power consumption, full fitting kit (fan, adaptors, cable, switch etc, plus instructions), proven system as used by motorhomers across the UK and throughout Europe
Expect to pay £250
Star Player #5
Elsan Organic Toilet Fluid And Rinse
2024 sees Elsan celebrating a century since it first started supplying sanitation products and today it has a wide portfolio of toilet fluids, cleaners and more – like this Organic Toilet Fluid and Rinse.
Using advanced biological technology, this can be used in your toilet cassette tank as well as for flushing (if you have a separate tank for flushing).
Elsan says: “By dissolving waste and removing toilet odours naturally, the chemical smell that has long been associated with caravan toilets has at last been eliminated… and replaced with a delightful mild fragrance.”
A typical dose is 60ml of fluid added directly to the tank for every 10 litres of waste tank capacity, then adding three litres of water.
Key features Environmentally safe, two-litre bottle, free from harsh chemicals, also available in 400ml containers
Expect to pay £14.50
Star Player #6
Blue Diamond 2L Uno Chem
An all-in-one product that is effectively a blend of Blue Diamond’s bowl and toilet cleaners, so it can be used in the top tank (if you have one) as well as the cassette waste holding tank.
Blue Diamond reckons there are up to 80 doses in each two-litre container and the fluids are particularly effective with hard water, also including limescale prevention among its properties.
Key features Biodegradable, formaldehyde-free, pH neutral,
Expect to pay £11.99
www.blue-diamond-products.co.uk
Star Player #7
Fenwick’s Top & Tail
Arguably, this was the first formaldehyde-free toilet waste chemical to hit the market. It can be used in a header tank as well as the toilet cassette, or just in the latter.
Fenwick’s says Top & Tail has a seven-day cycle at its most efficient. The formula also has a lubricating effect on key seals, also adding a coating to the toilet bowl – all helping to keep things as clean as possible.
Typical doses are 50ml for the top (header) tank (if fitted) and 125ml for every 20 litres in the waste holding tank, which should also be primed with two litres of water.
Key features 2.5-litre container, formaldehyde-free,
Expect to pay £18 (2.5 litres)
Star Player #8
Thetford Aqua Kem bathroom cleaner
A cleaner that’s safe to use throughout your motorhome or caravan washroom – including the shower and washbasin as well as on the toilet itself. Indeed, all plastic surfaces.
Thetford says it’s a “nature-based formula” that loosens dirt and limescale, including any soap residues, polishes and leaves a pleasant fragrance.
Simply spray it on, leave for anything up to seven minutes before spraying with water, then wiping clean with a damp cloth.
Key features 500ml spray, ocean breeze fragrance, can be used daily
Expect to pay £5.50
Star Player #9
Fenwick’s Waste Pipe & Tank Cleaner
Another great way of keeping any nasty niffs down is to make sure your leisure vehicle’s pipework and tanks – including toilet cassettes – are kept as clean as possible. That includes getting rid of any stains.
Used once a month it won’t only get rid of unwanted smells, it will also keep your toilet operating at optimal efficiency. Diluted, it can also be used on any surface.
Key features Can also be used in blocked pipes, one-litre plastic bottle, highly concentrated formula
Expect to pay £10
Star Player #10
Lifestyle Appliances Super Concentrated Blue Toilet Fluid
Unusually for a leisure vehicle toilet chemical, despite the Blue in its name, this is free of formaldehyde. It also comes in a plastic bottle that’s recyclable, offering 25 doses (per litre).
The fluid also has water softening abilities, making it particularly useful if you’re travelling in hard water areas. Typical dosage is 40ml per 10 litres of tank capacity, with a minimum of two litres to make sure any solid waste is covered. Typically, this will last for three to four days.
There’s a Green alternative, also providing 25 doses per one-litre bottle, that’s biocide-, enzyme- and probiotic-free.
Key features Suitable for all chemical toilets, one-litre container (25 doses), formaldehyde-free, non-staining dyes, cherry fragrance, made in the UK
Expect to pay £10.99
Star Player #11
Dometic GreenCare Tabs
More than five times lighter than carrying a two-litre bottle of toilet fluid.
Each tab is covered in soluble film making it easy to handle (make sure your hands are fully dry, though) and is suitable as a single dose for any typical 20-litre waste holding tank.
GreenCare is the more environmentally-friendly alternative to PowerCare products, also from Dometic.
Key features Suitable for all chemical toilets, still works after freezing and thawing, 16 tabs per pouch
Expect to pay £25.99
Over to you…
Do you have any advice on preferred toilet cassette fluids and keeping things fresh and clean that you’d like to pass on to fellow caravanners or motorhomers? Please feel free to add a comment below.
If we’re travellimg to/from site without using the m/h toilet en route, we rinse out the cassette and add water and a dishwasher tablet. empty and rinse at destination and .. one clean and fresh cassette
Only put products in flush tank if it is separate from your fresh water tank, which is not the case on many camper vans!
Try a small amount of Zoflora in the tank flush. Beats others hands down and no black sludge build up. Win win!
Steve Johnson says Like Dave Carter I used pink fluid in the flush for years however over time black bits were being left in the bowl. I stopped using pink and now dose my flush with Milton sterilising tablets about every third fill up. It’s cheap and very effective and has a slight bleach type aroma.
We used Thetford pink fluid in our Elddis caravan top tank and found that we were always getting black blobs every time we flushed. Many of our fellow campers had the same problem. With us this came to a head when our pump in the top tank became completely full with black sludge, necessitating the replacement of the pump. Since then we do not put anything in the top tank and have no further black gunge from the pump. We do not use this pink fluid any more.
We buy the stuff Aldi sell. Its the most concentrated fluid we have ever used, so I just stock up when it comes in the middle isle. Never had anyone ask me if its eco friendly?
For years we have had caravan insurance with Caravan Club and Camping & Caravan Club but never have they been interested in my skills or ability but since being with you I have been so impressed by your continuing efforts to improve my knowledge and ability -thank you.
Thanks for the fabulous feedback Malc. We hope we can continue to impress you with great service for many years to come! Liz
I use Wessex Chemical Factors Clear Blue Bio – lovely smell and goes in both the cassette and flush tank
Been using Solbio fluid for almost a year now, lasts well and love its eucalyptus smell. Plus if you add a drop to the flush tank you get that fresh smell every flush. Also run a diluted mix down your sinks/ shower to keep the pipes and waste tank clean. Great natural product.
Eight year old Thetford C260 and always used pink additive from one of the well known manufacturers, but last time out no flush.
Removed pump which was sludged up, and jammed solid. Apparently this is not unknown, so if not effective in neutralising effects of tap water, what is its purpose, (apart from a mild scent).
I’ve been told some caravanners use a low suds washing capsule instead as they’ve had similar problems, so any suggestions please.
Very happy with Solbio, breaks down waste very fast and smells better than anything else I’ve used over 31 years of caravanning
I rally often and consequently empty our cassette more often than average and also have been over 40 years enjoying my pastime. Having tried most products I find that Elsan’s double concentrate blue is streets ahead of anything else on the market. I have many friends that I go rallying with and almost all of them feel the same as me