Coloured Slate - Safe?

[Bugdozer]

You know the coloured type slate you see around ornamental trees at garden centres etc? It's normally slightly greenish or purplish looking. Is this safe for fish tanks or does the colour come from some sort of lethal dye? Anyone know?

 

[Peter C]

It's usually ok

Iv got a 3 foot slab of slate in my tank

Lake district slate is a natural purple colour so I'd say ul be ok

 

[mike455555]

id say its okay... but be careful i used it and it made me water cloudy so i took it out again. no harm to fish though

 

[Bugdozer]

I will try it and see then! I want to make a little shelter for my shrimps so they can eat their food in peace without the bloody tetras trying to steal it out of their claws.

 

[DrRob]

Slate that is naturally a certain colour is generally safe.

Slate that has been coloured is variable.

Just make sure you don't get shale, looks very similar but tends to break down very easily and leave a muddy mess.

 

[Bugdozer]

Slate that is naturally a certain colour is generally safe.

Slate that has been coloured is variable.

Just make sure you don't get shale, looks very similar but tends to break down very easily and leave a muddy mess.

I'm pretty sure it's not shale as it is used in an outdoor decorative setting. Problem is I have no way to tell if it's naturally coloured or not. It's the sort you find as small fragments a few inches across around the base of ornamental trees in garden centres. I suppose I could chip a bit off and if it's the same colour inside it must be natural.

 

[DrRob]

Aye, just belt it with something hard, that'll give you a fair idea.

Shale crumbles far more easily when wet, and can usually be scored with a piece of metal quite deeply if properly wet, wheras slate can't.

 

[Bugdozer]

I split a flake off it, and it's the same colour inside, so it must be natural. It's definitely too hard to be shale. I'm cleaning it now for tank use