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I wanted to give expanded shale a try for my growing medium. I know TXI has a plant in/near the DWF area so I figure there have to be some places in and around the area that carry shale.

Anyone have any luck finding some around the Austin area? I've tried Natural Gardner, they usually have it in bulk but have been out of it for some time and have no ETA for their next shipment.

Just curious if anyone has has any luck finding some nearby or has any suggestions, please let me know!


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i would be interested in 2 yards or as much as i can fit in the back of my Jeep Commander.  I can probably find a local business address for delivery. I live in Mexia, Tx so it would be half way between Houston and DFW.

I have been working with a rock supply in Bastrop TX. We are pricing Expanded Shale from TXI in 1/2 - 3/4 inch size, pre screened. It looks like it will be around 125.00 a yard FOB. They are looking to buy a 18 yard truck load. This size should give us the best price with no waste for use in our systems.



Sounds good Marty!

I wish I could get Living Earth to do the same.




Here's a picture of the sample i got. It's classified grade 'D' pile. Looks the same as your pile Rick.  I'm pH testing it now. Put a small handful in a quart jar with my 6.5 ph fish tank water. We'll see what happens in a week.  Still haven't gone to my local Living Earth yet. When i go, I'll bring a bag of donuts with me.

Here's the results from my experiment. I took 3 x 1 quart jars of my fish tank water (ph = 6.5) and tested the ph 1 week later.

quart jar # 1. added expanded shale - ph = 8.3

quart jar # 2. added new hydroton - ph =  7.6

quart jar # 3. added nothing - ph = 7.2


The same amount of expanded shale and hydroton were used. I suppose because i took the water out of the ecosystem the ph naturally raised itself somehow and adding shale or hydroton speeds up that process. 


I going to try and find a source of river rock next and run a test on that before i decide what to go with.

Wondering if a built-up biofilm will have a lowering effect over a longer term, for Exp Sh as well as Hydroton. You know, like insulation...

I have used Expanded shale from TXI as both an aquarium gravel substrate, a pond bottom substrate and as a wet-dry filter bed substrate. I get it from a feed/organic gardening store here in Plano called Wells Bros(on K street near Sam's club) for under $8 for about 40 lbs/.8 cu ft.  Since it is designed primarily for horticulture use, it is a bit dusty with a lot fines, and the largest grain size is about 3/8 inch.  It is fairly well sorted, and only a small amount  is smaller than about 1/8 inch.  Since it is made in cement kilns, it does have a fair amount of lime residue, thus it is quite alkaline.  When I put some in distilled water, the resulting Ph is over 8, like 8.4 probably.  Simple washing doesn't remove this, but I have used sulfuric acid to soak the expanded shale, and that removes most of the high alkalinity.  Since our tap water here in Plano is around 8.0 to 8.4, I'm not sure that worrying about the pH is reasonable.  I think the benefit of acid washing might be to increase even more the openness of the pore spaces.  I have gotten some Muriatic(HCl) acid to wash my next batches, as I think this would be even more effective in dissolving any calcium lime left in the pore spaces.  Calcium chloride is much more soluble than calcium sulfate.  I have not found using either plumbing grade sulfuric acid or pool grade hydrochloric acid to be harmful to my koi fish, but of course I rinse these away with tons of fresh tap water. I really like the appearance in my aquarium, as it is so natural looking, with a variety of neutral colors from light to medium to dark grays, tans, browns and terra cottas.  

 I think expanded shale is an ideal alternative to the more expensive hydroton or other more porous synthetic media.  It may be superior to lava rock cinders(scoria), as much of their porosity is non-connected bubbles inside the "rock foam".  My next move is to get a bulk yard or so of ex shale, via my sons pickup truck, since it is much cheaper in bulk with customer pickup. 

Living Earth, the only bulk supplier in Houston area, reportedly has now set a "Minimum 4 yards" on their delivery orders.

If you are wondering about a contact name and number to discuss this with them, Richard Stamper at 713-582-4816 has been helpful in the past.

Thanks, Rick.  I figure I'm just going to have to rent a truck from home depot and swing by there tomorrow morning.   It'll be nice to finally get going on the media!

Expanded shale at maximum weights a little less than about 1500 lbs per cubic yard(27 cuft/cuyd X 55 lbs/cuft), and there is a Living Earth bulk yard about 2 miles from my house(its actually right behind Wells Bros) so it shouldn't be too stressful to our truck.  One can always pick up orders less than the minimum delivery, but I think it's got to be in 1 yard increments to get the yard price.  The price here at Living Earth is $65 per yard, and the guy told me that since it's been dry, it now weights about 700-800 lbs a yard.  

Grrrrr... My Living Earth charged $110 a yard for the same thing. Yeah, Plano is right there at the source.

I was all set to rent a truck and head over to Living Earth yesterday... glad I called first, they only had one yard available!  Looks like I have to wait a week or go in the morning sometime this week if they get some more in.


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