Cleaning the grey water tank effectively
Keep the waste-water tank free of bacteria: Step-by-step guide
Grey water eventually forms incrustations and grease deposits in the waste-water tank. Malfunctions in technical parts and unpleasant odours can be the result. Therefore, the waste-water tank should be thoroughly cleaned at least once a year.
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Products for cleaning the grey water tank
The internet is full of tips on how to clean the waste-water tank. Vinegar, tooth-cleaning tabs or citric acid are advertised here. But: Do not use household cleaners to clean the grey water tank. These attack the seals, hoses and other components of the tank and damage them permanently. There are special products for thoroughly cleaning the grey water tank that are gentle on the material and harmless to use. Here you can find all the products for disinfecting and cleaning grey water tanks presented in this blog post.
Berger Fresh Tank Cleaner 1 litre - 2 in 1 cleaner for the waste-holding tank and grey water tank
Application: Waste-water tank
Amount of cleaner: 100 millilitres
Amount of fresh water: 5 litres
Application time: several hours
A powerful, concentrated cleaner for waste-holding and grey water tanks that removes incrustations, limescale and grease deposits, cleans technical parts inside and extends the service life of the tanks.
Thetford Duo Tank Cleaner
Application: Drain
Amount of cleaner: 600 millilitres / tank
Amount of fresh water: 50 litres
Application time: 16 hours
The bottle has a sight strip on the side to make dosing easier and a cap with a child lock. The liquid smells slightly of disinfectant when diluted. The product can also be used for cleaning the waste-holding tank.
Berger waste-water tank cleaner
Application: Waste-water tank
Amount of cleaner: 90 grams / 30 litres tank volume
Amount of fresh water: full waste-water tank
Application time: 8-10 hours
Fill the waste-water tank halfway with water. Dissolve the product in 1-2 litres of warm water and pour it into the tank. Then top up the tank with water and let the product take effect.
I recommend that you wear gloves when cleaning the grey water tank. You should also ensure that there is sufficient fresh air when using the cleaning agents.
How do I clean the grey water tank?
Depending on which product you choose, you either pour the liquid directly into the waste-water tank, into the fresh water tank or into the kitchen or bathroom drain. This way you can theoretically clean the fresh and waste-water tanks, as well as all lines and hoses, in one step.
It is important that you drive the motorhome or caravan for at least one hour after the cleaning solution has been applied. This allows the mixture to reach all corners of the tank. Then you let it soak in. So choose a period for cleaning when the motorhome or caravan will be moved anyway.
Note that you may only empty the water-cleaner mixture from the waste-water tank at a disposal station.
Additive for the drain
To show you exactly how cleaning the waste-water tank works, we cleaned the 90-litre grey water tank of a motorhome with Berger Fresh Grey waste-water tank cleaner.
First check whether the waste-water tank is completely empty. To do this, you can open the drain tap or look at the digital display. Then close the tap again.
Now fill in the cleaner according to the manufacturer's instructions. Our waste-water tank is 90 litres. That is why I use 270 ml of cleaner.
To ensure that everything is cleaned evenly, I put 1/3 of the mixture into the shower drain, the bathroom sink and the kitchen drain.
In addition, about 4 litres of water are added to each drain so that the cleaner also reaches the waste-water tank.
Now the motorhome has to be moved. Drive a curvy route and brake a little harder so that the cleaner reaches all parts of the grey water tank. Then allow the cleaner to soak in overnight.
The next day I flush the pipes again with some fresh water.
Finally, the cleaner mixture is drained over the disposal station. To do this, the red tap next to the waste-water tank must be opened on this motorhome.
Additive for the fresh water tank
If you also want to clean the fresh water tank, put the appropriate cleaner in there and open the taps to get a few litres of the cleaning solution into the hoses and the boiler. You then drive your caravan or motorhome with the taps closed. Then drain the mixture into the waste-water tank to allow the solution to soak in.
After the cleaning process, all pipes must be thoroughly flushed. To do this, drain the waste-water tank, fill the fresh water tank with water again, turn on all the taps and empty the waste-water tank again. This must also be rinsed thoroughly. Repeat this process at least two times until only clear water comes out of the tap.
Additive directly into the waste-water tank
If you only want to clean the waste-water tank, pour the cleaner directly into it according to the manufacturer's instructions. Add the right amount of water. However, this cleaning option is only practical if you have a portable waste-water tank. This is because tanks permanently installed on the underbody are difficult to access and usually only have an opening at the bottom. Afterwards, move the vehicle or shake the tank sufficiently and allow the mixture to take effect. Here you can find portable waste-water tanks in the Berger online shop.
As an example, we cleaned a portable waste-water tank here with Berger Fresh Tank Cleaner for the waste-holding and grey water tank.
To do this, 10 litres of fresh water are filled in. Then add 100 ml of cleaning liquid.
You should now shake the tank thoroughly so that the cleaner can wet all corners inside. The mixture must then soak in for several hours before you dispose of it.
How often must the grey water tank be cleaned?
How often you need to clean your grey water tank depends, of course, on how intensively you use it. If you go on holiday frequently, take showers and do the washing up in your caravan or motorhome, you should clean the waste-water tank 2 to 3 times a year. If you use it less often, cleaning it before the winter break is sufficient.
Conclusion: important cleaning
In order to enjoy your grey water tank for a long time, it is important to clean it from time to time. With a little effort, you can maintain the material and increase the service life of your waste-water tank.
