It's best not to draw from the bottom of the tank, use a floating inlet hose
Yes I know how the tank vac works, but you are better off not bothering with one and having a floating outlet instead.
Thanks all. I have now heard back from them.
Tony, I will have first flush, tank vac, floating inlet and a leaf screen - they all do different things, and it doesn't hurt to have them.
that sounds great, and filters on the outlet? 30 and 1 micron are the norm.
I will have filters - still working out which ones. Looking for cheap to replace and effective.
I also am looking into UV treatment. Not the fluorescent ones, because they need to be on all the time and hence lead to unreasonable power usage for off grid for power, but there are now LED ones, that only turn on when water flows which look good at initial glance.
I use the larger filters, available on TradeMe. They are easy to install and the cartridges last a long time providing your water is reasonably clear. a 1-micron filter will remove most bacteria and cysts so I have a 20 micron then a 1 micron filter. I doubt you will need any further UV sterilizing system unless you have very young or old people living in the house.?
look to be a good buy. You will need a 25mm connector to join them together, and 2 X 25mm male alkathene adaptors. Just fit them where the water enters the house as you don't need to filter garden water.
I have a piece of fine weldmesh over my outlet, about 10mm square spacing. It is attached with a couple of tabs/self tappers. I have a sock on my inlet after my first flush to catch any leaves/other debris that gets past the first flush (and some will) so no debris of any size that could block the outlet mesh gets into my tanks. But the mesh is removable anyway if something did happen to get past everything and out of the overflow. The U-trap is specifically there to stop mozzies etc from flying up the pipe.