I assume from 'rust', that you mean that dark-orange shade.
Do these guys jump at all ? I had 'spring-tails', (see another post nearby), but they were beige in color. I never saw them 'in' the water, they may have skipped tho'.
I used to just crush them under finger, whenever I went near the tank. Eventually they were gone.
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Angels, Black Mollies, Bristlenose', Clown Loaches, Cory Aeneus, Gibby, Guppies, Hockey-stick Tetras, Keyhole Cichlids, Otocinclus.