Rocks and Sand

[pankelephant]

I need a rock ID please. These have been found in and around a freshwater lake in Maine.

I'm referring to the darker rock; the others are a different kind.



This is wet.



I'm thinking shale, but I'm really not sure. I'll do the vinegar thing, but I know that's really inconclusive. Any ideas?

Also, the sand in our lake is gorgeous and I'd love to use it in my tank. It's fairly coarse as sand goes, with lots of pebbles. The lake is exceptionally clean; we aren't allowed to use any pesticides or chemicals - not even fertilizer. So two questions. First, is it possible to make it entirely safe for fish, and if so, how? Second, would I be able to plant in it? I'm not looking to do intensive planting; just mosses and low-light stuff.

Thoughts?

 

[NYgiantsRP]

Just scrub the rocks good with clean water, and rinse the sand like crazy. Just get the sand in a big bucket, get it outside with a hose and rinse rinse rinse rinse rinse rinse until the water runs clear. The plants will be fine.

 

[pankelephant]

Awesome, thanks!