What? Waxy Rocks?

[ashemely]

So, I bought this bag of large rocks from my local garden center. The rocks are advertised as decorative rocks, but they're just plain old rocks to me. Not so! I was rinsing the rocks off in hot water, because I noticed on the bag it said fish safe, not aquarium safe but fish safe. Anywho, while rinsing the rocks off, this waxy film started gathering on the top of the water. I am currently boiling the rocks right now, but I just wanted to check here if anybody has encountered this before, and if I should even try and attempt placing these rocks in the tank?

Thanx

 

[three-fingers]

Probably just due to where they were stored, never noticed that before, I tend to just pick up rocks from rivers or when I go for walks.

However, I would never boil rocks. They retain their heat for a very long time and it's very easy to get burnt. Also any gas pockets in the rocks could result in an explosion as the gas expands due to the heat.

Just pour boiling water from the kettle over them if you're worried.