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[Twiggz]

I say take the gex out and get your hands dirty. Pull what you can out of the tub (ie water bowls, branches etc) and grind the sand between your fingers and palms- will squash any remaining eggs and kill of the pesky pinheads.

As for avoiding in future- two options: feed them only males, or only offer females in cases where you know they will be eaten readily.

I have the same problem your querying from time to time, though in my milii tanks-but i'm lucky enough in that regard that i can drown them in water without causing any further issue for the inhabitants.

Good Luck.