Pretreatment for white

Hmm it made to make the titanium in white ink to adhere to fibers of shirt and believe only works with white ink as being an under base
There is special pretreatment for light color garments to make last longer

There are different formula pretreatments for light and dark shirts. Are you printing white ink on the white shirt? Its really hard to understand what you are doing, and what you are asking. Can you tell us what you are doing and what is happening? That way we will be more able to help what machine do you have?

I am using the Kodijet 603 with Yuhan-Kimberly Nano Colorants. Great inks when not using precoat but I think what I did was use black precoat instead of precoat for white. What precoat do you use for whites. When I washed the shirts the shirt without precoat came out looking just like it did when it was printed.

I dont think many people use your DTG printer and ink set I'm afraid

Isn't the Kodijet a Busjet?