Hi newbie here does it matter which brand of Eolys fluid that you put in the small tank?I have a ford focus 1.6tdci and found a brand called maddox dpf regeneration. when I went to the car part shop they did a search with the vin number and they said it had to be specific and was more than twice as much.

What could happen if I put this budget brand in....Also Ive watched some youtube videos on where the fluid goes and they show different filling points some fill from the fixed point on the top whilst some fill from the dangly flexible point which they say is the overflow, does anyone now the correct one or does it not matter...Thankyou

Did you ask how much is it Peugeot/Citroën? Over 10 years ago I got it from them, it comes with the kit for filling as well. Paid under £100 back then. 

maddox is 30 quid with the filling kit same as on ebay but from motor store want 80 quid just for fluid. I just want to know if you can put other brands in. 

As long as chemicals in it are the same I can't see why not. 

Yes, it does matter which type you use.  They are not all the same.  

I hadn't heard of Maddox myself.  (Used the PAT fluid from ebay with the green label).  But the website below shows how to check which one you need.  Peugeot/Citroen continued using Eolys when Ford changed to coated DPFs around 2009.

Maddox 1044 (EOLYS 176, Infineum F7995) DPF additive (2nd generation), particle filter additive, 3lit. purchase, prices: 21 364 Ft. Ft. (kauffer.hu)

(It's in Hungarian - but my browser translated it successfully)