Black Limpopo Sand

[Mo1959]

Hi. Does anyone on here use this sand? Wondered if it is completely inert or would I be safer just using play sand?

Maureen

 

[OldMan47]

I just did a quick Google on that stuff and the only person who made any comment about chemical properties said it would be expected to drive the pH up. I have no idea if they were right but by the looks of it, the sand is also very expensive.

 

[Mo1959]

Yes, thanks OldMan. I think I may have found the same quote. Said it fizzed when placed in vinegar which is usually an indication isn't it? I think I will go for pool filter sand instead.

 

[Essjay]

I got a bag of this. It does fizz with vinegar. So I tried a controlled test - two tubs of water, one with the sand, one without. Over the course of a week, the pH, GH and KH all went up in the sand tub relative to the control tub. Unfortunately, I've lost the actual results but I seem to remember that the pH in both tubs went up 0.2 overnight (to be expected on standing) then the sand tub went up a bit more. The GH and KH both went up by 2 or 3 as measured by the API test kit. The sand:water ratio was higher in the tub than would be the case in a tank, but even so, I didn't want to risk it.
So I still have a bag of sand sitting in the garage.

 

[Mo1959]

Thanks for that essjay. Have just emailed to hopefully manage to cancel an order before it is sent out. Have ordered some pool filter sand instead.