"Stuff"

[FishChick]

I have run in to this evil bright white "stuff" that seems to be growing in my gravle. I have had to remove some gravle because it makes all of the gravle stick together in huge clumps. Water is fine, fish are fine, but the white stuff just doesn't look good. It is making my pretty tank not look pretty any more. Any one know what it may be, how to make it go away, and where it may have come from?

 

[colesea]

Food that is rotting in the bottom of the tank. The best ways I know to prevent it are to gravel-vac during your regular water changes and cut down on the amount of food you're giving your fish.
~~Colesea

 

[FishChick]

It is not food, I checked that. gravle vac won't work with it, the gravel clumps are rock hard. That is why I have been pulling them out when I notice them.