what rocks can I use?

[kevfiz]

what type of rocks if any can I use in my tank?

 

[Byron]

Rounded river rock, which you can purchase at most landscape or quarry outlets, are usually very safe. And they can create a very realistic river or stream depiction. They come in all sizes from pebbles up to smallish rocks (6-8 inches across) and a variety can be very authentic. The rock itself is usually inert, meaning it willnot leech minerals like limestone into the water.

Calcareous rocks, like limestone, marble, lava (sometimes), etc. will slowly dissolve (slowly but consistently), adding dissolved minerals to the water, raising the hardness and pH. This is fine in livebearer or rift lake cichlid tanks where you want harder water anyway, but in soft water fish tanks it can cause real problems especially the more there are.

Wash the rocks well, under the tap, use a brush. Do not boil rocks, they can explode. There is of course always the risk of something having been absorbed over time by the rock (pesticides, chemicals, oil, etc) and leeching out. If you collect rocks yourself, avoid places where this is possible. I've not myself experienced this with river rock purchased from a landscape outlet. River rock naturally comes from a river, and the water has worn down the rock to the rounded shape, so it is less likely problematical.

Byron.

 

[kevfiz]

OK thats great thanks