Re: Substrate recommendation --Lapis Lustre

Greg Tong wrote: 
> in Aquatic Plants Digest     Wednesday, 7 February 1996     Volume 01 : 
Number 238

>After spending too much time looking for substrate, I thought I'd post the
>name of a brand that fits the bill. I have not been able to find the
>elusive "quartz gravel" and generic (and unnamed) fine sandblasting sand
>here in the San Francisco area.
>What I did find and have tested is a product by RMC Lonestar called "Lapis
>Lustre." It is an entire line of gravel and sand of different grades--from
>coarse aquarium gravel to 60 mesh sand. Take your pick. Hardjono put me
>onto the medium grade aquarium gravel and I have tested the #2/12, which is
>a very pretty yellow sand with flecks of pink and black. No shells, no
>vinegar fizz, and the composition of the whole line is the same.
>RMC Lonestar is headquartered in Pleasanton, CA and supplies Lapis Lustre
>to hardware stores. Its phone number is 510-426-8787 if you want to ask for
>a local dealer; I'd just call up the hardware store first. The price of the
>#2/12 is $7/100 lbs. Local aquarium stores are asking 50 cents/lb for the
>same thing, or $50/100 lbs.

Please forgive me for disagreeing, Greg, but Lapis Lustre is _not_ a safe 
brand name. RMC Lonestar digs most, if not all, of it right off the beach 
(around Davenport, I believe), and does nothing whatsoever to remove the 
shells. It is a lovely-colored gravel, with nice round particles. It is well 
sorted and free of dust, It has everything going for it but safety in a 
fresh-water tank.

How did you do your vinegar test? The bubbles one could expect from the 
strongest full-strength vinegar are very, very fine and subtle. A really 
bright light behind a clear cylinder is needed to see the fine streams of 
bubbles (if you can see them at all). Pool acid is a much easier and more 
certain test. It fizzes. Hardjono claimed his new substrate passed the 
"vinegar test" but I could easily see pieces of shell in his tank's new 
substrate, when I was over there last night. He can expect to do lots of water 
changes to keep his pH from heading toward 7.6 or above and his kH from 
rising. Perhaps it will be less problem in his tanks, since they are 
beautifully loaded with plants, and have low fish loads. They may be able to 
use the inorganic carbon as fast as it is released. I wouldn't bet on it 

I have purchased Lapis Lustre from several sources, and each time I have had 
to soak it in pool acid, stirring from time to time, until all bubbling 
stopped. This leaves bits of shells *still* visible, but their ability to 
dissolve in soft, acid water is so reduced that there is no problem with kH 
and pH creeping up after the treatment. Handling strong acids is not for the 
uninitiated, so don't mess with it unless you _really_ know what you are 

The nuisance of acid treatment has driven me to get all my gravel from the 
Basalite outlet in Sparks, Nevada. They usually stock the SRI Supreme gravel 
that comes from Sierra rivers. While attractive, it's not quite as colorful as 
Lapis Lustre, it is totally free of any limestone. If enough of us ask, our 
local stores would stock the SRI stuff and I could quit hauling it so far.



Wright Huntley (408) 248-5905 Santa Clara, CA USA huntley at ix_netcom.com