Ive read many websites which ask this question but none of them give a answer so I have ran a test myself ona Epson 7880 mainly to advise clients how many cleans to perform is they use my cleaning fluid or switch inks.
Firstly why should I use cleaning fluid when changing inks. The answer you dont have to, should the chemicle differences between the two inks be similar then their should be no reaction and no gelatinous residue created which will clogg tubes and heads. However there are no guarantees in life and noone knows how your inks are made.
With our inkforinkjet we know the formula is not too distant from OEM inks and as such you can happily use our carts to force OEM ink through the printer until your new ink hits the head and you will have no issues. IF however you are using another manufacturers ink we cannot be sure what forumla they have used. To be on the safe side flush with our cleaning fluid and then refill with our inks.
It matters not which method you use as long as you push enough ink through the system, I have noted ona epson 7880 7900 7890 sized machines then TWO POWER CLEANS are enough to push cleaning fluid through to the head and beyond to the waste tank. This would be enough to do an ink change.
INK USAGE :-
Based on a Epson 7880
Single head clean = less than 1ml per colour
Power Clean = 15ml per colour
Initial Fill = 45ml per colour