Pothos can have a hard time transplanting substrates. So your soil-rooted, store-bought pothos may not do well in your filter and take a long time to acclimate. However, clippings rooted in water should thrive in your filter.
I believe the level of difficulty with transplanting acclimation ultimately depends on the variety of pothos
I believe the level of difficulty with transplanting acclimation ultimately depends on the variety of pothos