deisel additive level low

Hi,
I have a 307 1.6 HDI. I have just purchased it. I am getting the message
that the Diesel Additive Level is at it's minimum. The book tells me to go
to the nearest Peugeot garage to have it filled up again. - Surely not!

What do I need to buy and where does it go? Also what happens if I don't add
any?

Cheers

 

This is the Eolys fluid, which is used to burn off the soot particles
in the exhaust filter.
If you don't bother to do anything then the filter will block, and you
will have to get a new one, shouldn't be much over £500, unless you
can get it exchanged at about £200.
The fluid is available only from Peugeot or Citroen dealers, in a 3
litre top up kit, so you can do it yourself. It is expensive,
something like £25 per litre.
The tank which holds the fluid is just in front of the NS rear wheel.

NB. filling the tank will not turn off the warning, that has to be
done with the appropriate software.