Help: Clumping Sand Bed

[Whatigot]

I had issues with Cyano and I just stopped dosing vineagar with my kalk and doubled my water changes until it was gone.

Not the same issue, but very easily related.
I would exepect that if the issue mentioned in the article is indeed the same as your experience that doing a couple extra h2o changes should do the trick.

Maries comment carries some good weight as well IMO.