Legal limits on bringing diesel back from Austria

With the price of fuel rising ever higher the petrol stations 30K away in Austria look ever more attractive. I think it saves around 5 euro's a tank . There are new petrol stations being built at the border to fulfil demand.

Is there any limit to the amount that could be brought back in fuel containers?

I'm sure theres some German law (As there is for everything) stating it, but I don't know of the limits.. Prob. like 50L or less

I saw one of those cop/border patrol shows on tv and they had some guy coming over from Poland with fuel in cans in the trunk...but I cannot for some reason remember what the limit is.

You're allowed to bring max. 20 litres in canister or metal container. Some lorry vehicles have very big tanks. The drivers can fill their tanks without getting any troubles, even if it's 1000 litres tank. With normal car (PKW) you can install also an additional tank but this you need to get registered in your car registration book. Then all's OK and you're allowed to have additional tank in your car. And nobody can bark against you if its filled with fuel.