Diesel fuel stabiliser.

Can you mix M16 and Startron - if you already have the tank treated with either?

Possibly the brands will try to tell you not advisable ... but I can tell you simply that they should be OK ...

When we treat fuels - we have no idea if any additive has been added before ... we use ours and no problems. The only occasion that I know of that can prove difficult is if GTL is involved - but you do not have GTL in any significant volumes ... in fact rarely used in blends at this time for EU / UK ..
 
I've used Marine 16 for several years now, have to use 10l cans to refuel as rarely in a marina nowadays. Always add the M16 to the can, thoroughly mixed then poured into the tank. Never had a problem for almost 20yrs.
 
Have used Marine 16 once, as a precaution. Every other year no additive. Fuel from marina, tanks topped up over winter.

Touch wood, never had an issue in over 30 years.
 
I work out the dose of Marine 16 required for my tank, put it into an empty 5L jerrycan, fill it with white diesel, then add this overly rich pre-mix to the tank.

If my tank was already full, I would put the M16 into the jerrycan before siphoning some fuel out of the tank into the jerrycan, a quick shake then back into the tank.
 
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