Adhesive for gluing rocks together?

[kampkomfort]

BROKE STUDENT ALERT!

I need ~50lbs of base rock for my 55 gallon FOWLR tank. I just can't bring myself to pay pet store prices for "dead" rock. I've check out the alternatives:

Aragocrete--messy, curing is a hassle
Limestone--can't find it ANYWHERE here
Lava rock--can't find anything but the 1" diameter stuff

So far, my local Home Depot has not been much help...no Southdown, no limestone or large lava rock, no brown gutters for hood...and area landscapers don't have anything of interest.

I thought that maybe I would buy a bag of the small lava rock (this stuff is not mined, it's man-made) and glue many of them together to create custom, unique shapes. Seed it with live rock, and hopefully it would look ok after some time.

Any ideas on this? Any particular adhesive that would be well-suited to gluing very porous rock together?

Sorry for the long post...

 

[kampkomfort]

Would this do it?

OSI Multipurpose Construction Adhesive

It's waterproof (inert?) and $1 at the Home Depot. Any ideas?

Thanks.

 

[kervina]

Personally, I only use adhesives that specify they are safe for potable water. I haven't run into any problems using that rule of thumb, YMMV.

 

[livingstone]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by kampkomfort:
<strong>I just can't bring myself to pay pet store prices for "dead" rock.</strong><hr></blockquote>

Buy base rock online. Harbor Aquatics has an ad right here on reefs.org for fully cured base rock at $2.00 a pound.

 

[newreefman1]

the epoxy to use is Aquamend. Get it at home depot in a green plastic tube. its like 3 bucks. I always have a tube or two around.

Same exact stuff they sell in the LFS for 3 x the price.