IIRC, the "earth friendly" products are simply made from plant-based surfactants and perfumes, more often.
Unfortunately, this could mean they're made from palm oils/sugars, and contributing to that only keeps the destruction of rainforest at an all time high.
These plant-based surfactants often aren't as good as the real deal, and therefore, these products often perform the worst out of all detergents.
As for powders not completely dissolving, thats something thats based on how you add the detergent, like whether or not your pre-dissolve it, water temperatures and even the cycle times.
In hard water, the washing-soda in the detergents will often form a precipitate of the calcium and magnesium minerals, which may very well be the cause of your buildup.
