A gentle suggestion: backflush and/or chlorine-treat the filter, since the sugar the filter took up will serve as bacteria food.

p.s. Does First Need silver-coat their carbon?

“If you filter a coke, for instance, it will still be the same brown color as it went in,…”

Hey, that sounds like a fun experiment!
Hmm. I don’t have any coke around. How about a nice sticky grape Aldi soda? Extremely carbonated and purplish… lot of natural and artificial flavors… not one but several artificial and natural colors… high fructose corn syrup…

OK, here it goes, pure soda… up the First Need filter tube… And it comes out….. CLEAR! Wow. That just looks amazing.

But what does it taste like? All the color is gone… the carbonation is totally gone. There is a very slight taste of sweetness… like corn syrup. So it didn’t get all that liver-loving high fructose stuff out.

Still that’s incredible (OK, I get astounded easy). And now First Need has an even faster flow filter out for the same weight.