Bathtub ring, essentially, 4 letters
Build-up in an aquarium, 4 letters
Definitely not the elite, 4 letters
Film you don't want to see, 4 letters
Growth on some ponds, 4 letters
Man-bashing 1968 manifesto by Valerie Solanas, 4 letters
Napalm Death's debut album, 4 letters
Pond surface, perhaps, 4 letters
Scrubbing bubbles' target, 4 letters
Shower-door buildup, 4 letters
Soap ___ (bathroom grime), 4 letters
Soap ___ (mildew's cousin), 4 letters
Soap ___ (shower buildup), 4 letters
Spray cleaner target, 4 letters
Surface layer of impurities, 4 letters
The head on beer, essentially, 4 letters
The lowest of the low, 4 letters
Worst of the population, 4 letters
A film of impurities or vegetation that can form on the surface of a liquid, 4 letters
Tone down, in painting, 7 letters
The application of very thin coat of color over the surface of a picture, 7 letters
Bathtub ring with no discernible cause?, 15 letters
Like the greenest pond, 9 letters
Not really respectable, 6 letters