Grey water tank location and pump

I have been concerned about having to put the grey water tank under the vehicle due to the possibility of it freezing in winter.

I have now found a couple of methods that will make this unnecessary.The first is a dedicated pump. FloJet Waste Water Pump

The second is a fully enclosed.  Saniflow waste pump

The FloJet is smaller and cheaper but the Saniflow is designed to fit under the shower tray and also as a separate inlet for the sink which will mean it empties quicker.  The FloJet is 12V while the Saniflow is 240V.

I get the Bus tomorrow and will be able to start looking at the layout properly at which point I will decide which one to get.

With one of these pumps installed I can keep the Grey water tank inside the van ensuring that I do not have any freezing issues over this winter.  I am hoping to be able to situate the grey tank under the sink.

The power to the pump itself will be linked into the light that I will have in the shower.  So when I switch the light on the pump will come on.