Is this pulverized limestone OK to use?

[LockeOak]

I picked up a bag of pulverized limestone from Home Depot today with the intent of using it in a RDSB. It was 50lb for $2.50. Can anyone judge if it would be ok for this use? The texture is pretty fine, I would call it sugar sized or smaller.

Brand: Decor LawnLime by Imerys, Roswell GA

From the back of the bag:

Limestone / Dolomitic Limestone

Neutralizing value 90%
90% Calcium Carbonate Equivalent
50% Calcium Oxide Equivalent
Derived from:
30% Calcium Carbonate and
21% Magnesium Carbonate

Calcium Oxide 34%
Magnesium Oxide 10%
Elemental Calcium 24%
Elemental Magnesium 6%

[JCR's Reef]

If I remember right there is a thread on here talking about it but I cant remember what the title is. Try doing a search for cheap sand alternatives. I'm pretty sure its O.K. if it has calcium on the outside of the bag.

[LockeOak]

Yeah, I've seen threads on another brand of pulverized limestone, but not this one. I'm pretty sure it's ok to use, but I want to make sure. I'm mostly concerned about possible pH/alk changes it could cause.

[bertoni]

That description says it contains a lot of calcium oxide, which is quicklime. I wouldn't use it if it contains quicklime, which is effective kalk powder. You could mix a bit of it into a volume of water to see what happens to the temperature and pH. I'd be careful with it. Quicklime can release a lot of heat.

[LockeOak]

I don't understand how these "equivalents" and neutralizing values work. Do they mean that it contains quicklime or that the alkali effect is equivalent to that much quicklime?

Edit: I mixed 1/3 cup sand with 1/3 water, no warming or bubbling detected.

[TCU Reefer]

I've read about plenty of people using this sand from HD with no problems. I was actually there today looking for some to set up a RDSB but was unsuccessful.

[bertoni]

I can't tell from the label. I suspect it's not quicklime, but I'd rather be safe than sorry.

[Randy Holmes-Farley]

I believe those are all just odd units of measure, and it is calcium/magnesium carbonate. It is likely OK to use if the particle sizes and shapes are OK

[Boomer]

Randy is correct. Often mineralologists and petrologists give ion concentrations as oxides. Most rock assays are as oxides

Chemical Composition of Granite


Silicon dioxide 70.18%
Aluminium oxide 14.47%
Potassium oxide 4.11%
Sodium oxide 3.48%
Calcium oxide 1.99%
Iron II oxide 1.78%
Iron III oxide 1.57%
Magnesium oxide 0.88%
Water "molecule" 0.84%
Titanium dioxide 0.39%
Diphosphorus pentoxide 0.19%
Manganese Oxide 0.12%

[LockeOak]

Great. Thanks guys, I'm rinsing it as we speak to get rid of the finest of the fines.