Our indoor doggage (small poodles, 13lbs) have one of those water fountains with the built in filter. I thought it was overkill but SWMBO insisted. The activated filters were $$$ so I used my aquarium charcoal and just refilled them.
Well since dog slobber/back wash overwhelms them in a few days I just change out the water now after a cleaning.
If I had the bowls, the dogs would always be putting there squeaky toys and chewys in there to "soften" them up. Ewww!
Come to realize that anything dog related should be made from heavy gauge stainless steel.