I have 2 Harlequin rasboras that have each turned up with a tiny white speck on their lower lips.
Water is changed weekly (25%). Gravel is vacuumed bi-weekly, at which time the spong filter also gets cleaned.
Ammonia is 0, pH is steady from week-to-week at 7.2, nitrate (20 gallon planted tank) is steady at 20 ppm, temperature 77 degrees.
The other 5 rasboras and their tank mates (5 ember tetras, and 3 albino corys) all look fine.
Any idea what this might be?