Masking Fluid Marker Pen, watercolor

When I was using this pen when I was painting with watercolors, I noticed that the masking fuild from the pen would make the fully dried dr phil martins waterproof matte ink soluble and would be picked up when I remove the masking fuild when it was fully dried. Now, I dont mind that much, I just redo the part that was removed, but I thought I should metion because that was what happened to me. Otherwise, it works really good, you can fill up the tiniest parts. It's kinda hard to pick up, but you can use an easer to make it easier.