Is a Syphon the answer

Every Dutchman I ever met carried a plastic watering can for jobs like that.

As we do for topping up the motorhome tank, easy and cheap!

David 

I adapted a spare pump we had, the type that plugs into the van and drops into the Aquaroll, to fill our toilet tank as I struggle to lift any water container these days.

I removed the plug in bit, extended the 12v cable, fitted a push button on/off  switch and plug the cable into one of our 12v sockets.

I believe you can buy such a pump ready made.

Four of my five Eriba's have had an onboard tank. I have filled them all with a watering can.

Colin

Physics would demand that the transported water container level would still have to be ‘held’ above that of the onboard tank if the siphon was to work. We use a 10 litre plastic jerry can and an electric pump.

We had a caravan with an onboard tank for years. Never travelled with it full, as it “pitched” when towed by our short wheel base Jeep. Simply filled it up on arrival at site with a hose pipe, then topped it up each day with a watering can.  Easy peasy. This is what a lot of MHs do nowadays, if they aren’t going off site, and it’s a lot easier now the Club have put specialist service points in. 

What about a drill operated water pump with a couple of lengths of hose pipe. £20 from amazon or Halfords

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