What is the best water system sterilizer?

I have been happy with Puriclean. First used it when the water system became tainted by a chemical taste on a previous van. Sorted it fine

We had a recent thread on the topic which I can't find but the consensus was to use Puriclean which contains a non corrosive based chlorine product  (Milton is corrosive.) Although I'm reliably told by my OH that's he's recently been using a Lidl product which is much the same. It's best to check the chemical ingredients and how they react with components. Some can corrode metals or leach out a "tsp" taste in plastics etc.

Maybe someone can find the recent thread?

Milton contains sodium hypochlorite (bleach) which, certainly, Alde warn against using in their systems because of its corrosive properties.  I assume the same applies to systems using the Truma combi-boiler. Although it's a very weak solution, over time it clearly will have a detrimental effect.

Puriclean is a much safer option.

Just looking in as I noticed I used the wrong initials for TCP! There are notes about this "taste" on the Puriclean web site, Puriclean contains chlorine dioxide a different compound from Milton's sodium hypochlorite mentioned by R&R above. It pays to read the notes. 

I use puriclean although it does leave small residue of chalky like sediment. To quote Janet Webb of Morcambe & Wise fame, "it never did me any harm".

May be considered pedantic...

When flushing, if you have a fresh water hose, fix to shower or other tap (if possible) lead hose back to Aquaroll/container.

Circulate water round system/leave for a few hours rather than just fill and leave.

Can also use the opportunity to test water heating system to circulate hot water.

I feel flushing and circulating is far better than just fill and empty and cleans hoses too but that's just me.

Another Puriclean vote.

I've used Milton every year in the caravan i bought from new 9 years ago without any problem.

We use Milton too, and have done everything year since we started in the van. Never had any problems (and, horror of horrors, we actually drink water straight from the van tap - well, via a glass, obviously!) 

Have given our system (4 year old Lunar Clubman) the Milton treatment a couple of times but we usually buy a new 5 litre bottle of spring water from the local supermarket for drinking water then refill it on site.

Are we running any risks by not sterilizing the system more regularly, bearing in mind we usually use site facilities for washing etc, and we do change the system filters at least once a year?

Used puriclean, not convinced it did much but better safe than sorry. 

The issue is the water traps built into the water system in vans being left damp when laid up. Being a bit belt and braces I always extensively flush with hot and cold before using any water. 

I also bleach the waterhog once a year and syphon it out through the hoses. 

Always drink site water from van tap, not dead yet.