Rocks

[FishGO]

Hey guys,
 
How interesting is this topic going to be... ROCKS! Anyway im looking to add a few fairly large rocks to my aquarium and im just wondering if this will upset the chemical balance in my aquarium? No fish yet in it and about to start cycling but really think it would be a cool feature fitting with every single other thing about my tank.. which is homemade!

 
Thanks everyone for all your help recently!

 

[eaglesaquarium]

That all depends on the rock.  Some will, some won't.

 

[DrRob]

This is where the long term plan gets important. For fish like malawis limestone is fine, for soft water fish it's a disaster.
 
If you know what the rock is then you're generally off to a good start. You're trying to avoid leeching heavy metals into the tank, crumbling soft things in the water and dissolving rocks in soft water tanks that messes with the chemistry.

 

[Lateral Line]

I posted another message a short while back which I can't find right now. The rub of it was, deep igneous rocks, granites, gabbros etc are generally neutral and safe. Intrusives and lavas also. High grade metamorphic rocks are also good, gneisses, schists etc. With igneous and metamorphics, you need to be a little careful if the rock is veined, the veins can have inclusions which can be problematic. It is sedimentary rocks where problems start. Some of these can leach metals into the water and limestones in a soft acidic setup are deffinitely a bad move.