I've hit it with Affresh now. I will say it has a lasting lemony scent that makes the dishwasher seem cleaner. I did clean quite a bit of crud from the tubes that feed the upper arms. There is no approprite size brush for this at the hardware big box store. What will work is a brush set made to clean pet drinking fountains (sold at Petsmart or online), a test tube brush, or a brush set sold to clean bird feeders. Staying with the Palmolive Eco+ gel detergent, no evidence of new white chunky buildup... It might've been cheaper to just replace the arms, but then again the new arms might've been clogged by what was hiding in the lines.
Thanks for the assistance!