do you know which types of crystals are safe to put in a fish tank?

Question

I have been looking all over the internet, to see which ones are safe to use.
And all I keep finding is conflicting infomation.
I have to be extra carefull as I have a lot of snails and I don't want to mess with ph too much(as this causes shell erosion). Nor can they have metal in them.

so if you do answer please could you state where you got your info from (so I can see if it's a web page i have already read)
or if you use crystals in your own fishtank and how long you have used them in there (then I know it's tried and tested).

thank you very much for your help.

p.s i know i normally let the you guys choose the best answer, but this is a bit more serious so I will choose this time.

It is a freshwater tank.

Answer 1

Your best bet would be to use plain quartz crystals. This is pure silicon dioxide, so it's inert. Quartz goes into the production of the glass in your tank, plus it's may already be in your tank if you use the natural colored tank gravel (albeit in smokey quartz which contain some impurities which give it the brown/gray/opaque white color). Quartz also forms the "sand" in sandstones like what fish stores sell as pagoda stone - an unusual sandstone made of of layers with different erodability - this gives the edges a "sculptured" look. I wouldn't advise collected sandstone, as some formations (especially near coal-bearing veins) as these can contain iron pyrite, which breaks down into iron and sulfur, decreasing your pH.

If you're from anywhere near Arkansas, you may even be able to collect your own, as this state is one of the leading producers of quartz crystals in the US. They do have a reddish clay surrounding them but this can be cleaned in an oxalic acid bath (you can get the oxalic acid through lapidary suppliers, sometimes through drug stores/pharmacies).

Another possibility is dolomite - this is a calcium-magnesium carbonate which are both minerals that can be used by the fish and snails, although this breaks down very slowly (unlike calcium carbonate, which is found in the forms of limestone, calcite, aragonite, marble), and which should only be used in tanks for cichlids, saltwater, or other fish needing higher pH levels.

You can combine the two if you get (or collect) Herkimer diamonds from New York - these are very pure, double terminated (pointed at both ends) quartz crystals in a dolomite matrix.

I've also used a few pieces of microcline in a tank without any harm to the fish. This is an opaque blue-green stone that's made up of potassium, aluminum, silicon, and oxygen. Aluminum may react with the water, but it only becomes dangerous to aquatic organisms if the pH approaches 5.0.

Answer 2

Any crystals would be fine to put in your tank as long as they are first boiled. All crystals contain metals, that is what provides coloration, but all metals are very minor in quantity and would not move from the crystals, into the water. Any crystal you can find will work in your tank, just put it in a pot, put enough water in it to cover it, and wait for it to come to a boil, remove the crystals, let them cool, and decorate your fish tank. They will not affect your pH because there is not enough calcium in their composition.

Nosoop4u

Answer 3

No real ones. They have trace elements and minerals- they ARE a mineral. If you want crystals, get synthetic replicas and make sure they're fish safe! Silicone or plastic would be your best bet.
If you're going for substrate, it is better to use a sand or gravel bed anyway. If it's for decoration, pick up some dead coral. It's attractive, and safe for your tank inhabitants!

Answer 4

I wouldn't use ant crystals in a fish tank that aren't meant for it as the could have stuff in them that would harm your fish.If you look around at fish stores you could probably find stones that resemble crystals meant for a fish tank that would be safe.

Answer 5

What are you looking for rocks? like quartz, onyx diamonds, emeralds, ? None of these will mess up your water.

I am not so sure about your question here.

Answer 6

Is it a marine or freshwater fish tank?????????