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Graf Carat 4800 litre underground rainwater storage tank designed for installation below ground to serve commercial or residential premises.
Why buy this tank?
The image at the top shows a Carat tank with a cutout to show the interior construction and an illustration of a tank with filters and an external pump available from rainwaterharvesting.co.uk in a typical garden setting.
What do I get?
About the Tank and Graf
The Graf Carat tank is the largest tank of its kind in the world to be manufactured by injection compression moulding. This technique provides the tank with unbeatable stability and ensures that each component is produced with the highest accuracy. Graf have invested €20m in their factory near Freiburg for the Carat range, introduced in early 2007.
Like the Graf Hercules, the Carat comes in two halves so you can carry it through tight spaces even dorways.. (and so we can stack many of them on one pallet for bulk transport). A centering bolt on the tank flange makes assembly accurate. The quick knock-on connections and the patented seal laboratory tested for 25 years ensure there are no leaks between the two sections... and yet you can disassemble it if you like. The material used is a PE variant called Duralen.
Connections for underground installation:
Holes are pre-cut in the turret or dome for connecting the filter inside the turret. We recommend use of British standard 110mm brown piping (more accurately 4.25 inches or 108mm external diameter) as supplied by builders merchants like Jewson, Wickes etc. If you are using 110mm piping between your roof's downpipes and the tank, and between the tank and the drain or soakaway, then you have no worries about compatibility of pipe sizes.
|Compare the Carat S Tank sizes|
|Tank||2700 Litres||3750 Litres||4800 Litres||6500 Litres|
|Weight||120 kg||150 kg||185 kg||220 kg|
|Half Height ie before assembly (for access)||700mm||790mm||910mm||1050mm|
* The half height is a useful dimension if your site is at the back of a house and you have to get the tank through the doors of the house. The Carat is shipped in two halves with the turret separate. By tipping the half tank on its side you and a colleague can walk it through a narrow door. Your door width needs to be marginally wider than the half height shown.
1) Bit more leeway on the tank depth: Opt for a Maxi sleeve giving an extra 100mm of adjustment.
2) Support car traffic: (but not trucks and HGVs) when fitted with the optional dome and cast iron lid.
3) Deeper holes: You can compensate for a deep hole with a tank turret sleeve extension which extends the height of the pedestrian dome shaft PE lid by 1000-1500mm