Member - Doug T (QLD) replied:

Gday mate
I got one of those water tanks for semi-trailers and it just fits under the bed in my troopie, I run a hose out to a tap on the rear bumper and also run another hose from a T to a 12v pump so i can shower as well ,the tank is 80 liters and cost $110.00 www.bmackay.com.au/dp/tank.html

Peter 2 replied:

depends on how you mount it, the normal position would be flat on the floor, with the two bungs towards the bottom and the filler uppermost. those two bungs are the outlet (s), usually only use one in a vehicle.
The threaded hole in the big flat side is the breather, drill a 1/4 " hole in the bottom of the recess and then thread a fitting into it to take the pipe away to the highest point inside the vehicle, if temporary installation cable tie it to a grab handle or top of cargo barrier

hazo replied:

Hi Brew,
The large hole on the flat side is the top breather, the large stalk halfway up the end is the filler and the two small ones are outlets, usually only one of these is drilled out,the one not drilled can be used as a drain by fitting suitable short hose and tap after opening up witha drill.Same setup as most caravan tanks.
Brian

Member - Ray (SA) replied:

Do you need some sort of filter for the breathers?

Member - Doug T (QLD) replied:

I forgot to mention that I use it upside down with breather taps etc and to fill it i force water backwards , as shown below
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