If you fill a just-flushed pen with ink, it will write lighter and more dry for a page or so, untill you go through the diluted ink in the wet feed. Diluting an ink with water dilutes any surfactants that enhance flow and dilutes color intensity. That could be your culprit. Either keep writing for a while or let the pen sit unused for a day or two and see if that helps. The feed should dry out slightly, at least with the air inside the cap, or even more so with imperfect seal, and the ink will concentrate.
I think you're right. Thankfully my ink seems to be back to normal (i.e., darker & wetter), now that I've kept writing for a while without flushing my pen again. Thanks so much for the suggestion!
I find that the Noodler's inks that are at least partially water resistant can throw a pretty heavy precipitate if kept for a long time or in a cool room and a LOT of shaking may be required to get back to the original color and behavior. Make sure the cap is really on tight because you may be shaking for a minute or two and we don't want accidents. You probably should wipe the mouth of the bottle once you carefully open the bottle and from a distance pop the bubble of ink that may be there (I use a tissue as a shield). If bottles of Noodler's are not tightly closed enough water can evaporate to change the flow significantly and I worry about the batches that came in plastic bottles when they ran out of glass ones. That said, I took about 10 years to go through a bottle of Walnut and it was just a tiny bit drier-writing at the end. My probably 12 or more years old bottle of Noodler's/Swisher Aquamarine needs heavy shaking before being used (sparingly as it is unobtanium) but then writes beautifully for months in a Pilot Metropolitan B nib.
Is that so? I'll definitely keep that in mind then, when I make future purchases of Noodler's ink. I do try to screw the cap on as tightly as I can & I also wipe the mouth of the bottle every time after I open it. Also --- wow, that is a long time to be using a bottle of ink; I can only hope I'll manage to take care of my ink well enough that they'll last for that long. And yay I'm also using a Pilot Metropolitan w/ this ink; I have a stub nib & the ink shows beautifully.
Ok, this is kind of on an unrelated note, but does anyone know how traveling could affect ink? Specifically, traveling by plane? I'm going to college so I'll be expecting to do that pretty often, & am curious if traveling by plane frequently has any effect on ink properties.