Type of stones for tank - whats ok?

[MoxieGrrrl]

In addition to the color gravel I am trying to decide on (tougher than I thought it would be), I am looking at adding some stones for accent pieces...

One of my favorite stones is malachite (which looks like solidified mercury - smooth and dark silvery gray). Also partial to amethysts.

I assume that most stone do not leach anything, but are there stones that have properties that would be dangerous to fish? I certainly wouldn't want to add anything like metal, but wondered if there were any big no-no's for stones?

Thanks for the help!

 

[Apocalypse_Gold]

Nix the malachite. It is a copper ore.

 

[FishLover14]

Get all natural rock sculptures made for fish.

Dan

 

[MoxieGrrrl]

Dang. That more than sucks. Not that the natural rock sculptures aren't nice, they are just so... common? Anyone have any suggestions on adding some personal touches or is it pretty much "only buy things from fish stores" and that's the end of it.

It's just that neon-painted ceramics aren't really my style. Call me weird

 

[FishLover14]

Hey i dont mean those neon painted ones my lfs sells blackish brown colored rock sculptures with 2 entrances. They are a little expensive but beautiful!


Dan

 

[MoxieGrrrl]

LOL, no I know you meant the ones that look real. It just seems like if I want to add a touch of sparkle the only way to get it is to use the very fake looking gems or get those painted ceramics - neither of which I am thrilled with. Was hoping I could add natural polished gemstones (like red jasper, adventurine or blue quartz), but obviously want to stay away from something that will harm the fish.

 

[theatrus]

I believe quartz, as long as it doesn't have too many metal veins, would be ok. Most gemstones would be ok.... LFS rock is just so absurdly expensive. I can get most rocks for $0.15 / pound at a rock yard (or free from your property), but LFSs charge sometimes $8/pound 8O

I have a combination of calcium carbonate base rock, granite, and lava rock bits in my FW tank. Just be careful if you're trying to keep a low pH or soft water. Some rocks (like CaCO3 based ones) will leach out rapidly and give you a nice pH of 8.2 and 10-15KH. Great for reefs or cichlid tanks, not so great for your discus.

 

[rubysoho]

you can always go hiking and find your own. Then you'll have the satisfaction of knowing your peices weren't bought.

 

[MoxieGrrrl]

I guess I have just become scared to add anything that didn't come from a shop by everything I've read. I'm sure some of it is said so no one sticks the wrong thing in the tank and killed everything, but was looking for alternatives... I work for a company that actually uses all sorts of stones so I wanted to know which ones I could use. Mostly river rocks (black basalt) and some gemstones.

 

[QTOFFER]

Malachite is a copper ore and a carbonate to boot - it would most certainly be toxic and change your water chemistry. However, the stone you describe sounds more like hematite - an iron ore. I'm not sure whether hematite would leach iron into the water or not.

Quartzes should be safe for the tank, and there are lots of different colors to choose from (amethyst, rose quartz, citrine, tiger eye). Obsidian, or Apache tears, should be OK too. I love sandstone, red jasper, and petrified wood in the tank. Most of these are available for alot less money at your local stone supply.

BTW, this neat site shows the chemical composition and properties of all kinds of minerals.
You can look up a particular mineral by name or by class in the left hand frame.
http://mineral.galleries.com/default.htm

 

[MoxieGrrrl]

Fantastic, QTOFFER, great site - and you're right, the malachite is the green stone, I did mean polished hematite. Confused the two, my bad.