CPs and Sand

[SirKristoff]

Now ive used sand before in my mixtures
always horticultural sand
i want opinions from experianced people on this
i went to an old pet shop i worked for, and i was wondering if this would be fine. this is just a small amount of it, i bought a large amount for some other plants i have

 

[herenorthere]

There are a lot of things other than quartz in there and some people worry about that. But it doesn't look like a sand that would include calcite or other other mineral that would have a big effect on pH or TDS.

 

[SirKristoff]

AFIK i know it is beach sand so im not 100% sure what it has in it....If i had vinegar id test it

 

[BigBella]

It should be fine. Simply wash it up and it's good to go. Too many make a big issue of soil additves. If you've ever seen some of these plants in the field, you'd be surprised at how poor the compost is and how loosely the plants themselves are anchored.

One thing, though, and I am not joking about this -- taste the sand to ensure it's not contaminated with any salts; though that is unlikely, since pet stores often have to deal with critters as mercurial and as mineral-sensitive as carnivorous plants . . .

 

[SirKristoff]

uhg its lapis sand. i doubt its safe

 

[BigBella]

It's unsafe to breathe, from the silica itself but I also doubt that most of the crap we use to grow these plants is safe.

Excuse me, it's time for a shot of Superthrive® and to huff perlite . . .

 

[swords]

Wow! That's some really nice looking sand, I'm jealous! We can't get anything but Playsand around here at the hardware shops (so fine it chokes the roots).

You said you got that stuff at a aquarium shop? I'm gonna haveta go looking at the old LFS, thanks for the tip!

 

[SirKristoff]

so is the stuff safe for CPs or not

 

[herenorthere]

Lapis, as in lapis lazuli? Are the dark grains blue?

 

[SirKristoff]

Its Lapis Lustre i dont think its the gemstone herenor

 

[SirKristoff]

Here is a macro shot of some of it
some of the black specks are blue upon closer examination

 

[Not a Number]

Well from the macro it looks like the sand has been well polished, either from surf or more likely a lapidary drum. Most of it looks like silica and quartz except the grain under the large whitish grain top center.

I don't know what sort of abrasives are used for lapidary polishing but it should have been rinsed out if you're supposed to use this with critters.

There might be limestone or bits of shell in there if it came from the beach.

Otherwise superficially it looks like the horticultural sand I get.

 

[bucky78]

I have used pool filter sand without any ill effects and it is relatively cheap. Just wanted to throw that in there.

 

[SirKristoff]

It does have small chunks of shells in it but not too much. I took a small amount and washed it, it was clean...doesn't mean I won't wash it before I use it though. The stuff is for fish tanks and I saw it in the salt water tanks as well as the fresh water.

 

[swords]

If you can see bits of seashell in it it might not be good for acid loving CPs but things that get along on neutral or slightly alkaline soils might like it. If you're unsure about it pot up something expendable and watch it or even run some water on it, let it sit overnight and then do a PH test on the water if you have any of those aquarium water testing kits.

I'm just itching for some of that sand to use on my living stones and cacti, heading out to look for some tomorrow!

 

[SirKristoff]

Haha swords, I got a 10 pound bag of it for 5 bucks. So I can just repot my succulents and cacti in it if its not cp safe. The bits of shell are so small and miniscule idk if they would care. Barely even noticeable

 

[DrWurm]

That looks a lot like the horticultural sand i buy.

 

[swords]

$5 per 10# sack is my kinda price! Some of those aquarium gravels can be rather pricey (Flourite).

Where are you guys finding stuff marked as "horticultural sand" or is it marked as something else? The nurseries/hardware stores we have, all sell play sand or Mosser Lee's decorative "silver sand" and "desert sand". All these are extremely fine salt like grains and very quickly compact into a hard-pan mud flat in a pot. Ariocarpus fizzuratus might grow on a mud flat/flood plain in the wild but in cultivation it's not such a great thing to emulate.

 

[grumpus]

I went with pool filter sand; it's what they use at UNCC. It's pure silica and it's only $8.99 for a 50 lb. bag at pool supply stores around here.

 

[SirKristoff]

Still wanting to know what CPs exactly it might safe for
im trying to as a top dressing on a ceph since ive have heard they grow near some brackish water areas