The Ultimate DIY Rocks!

[Chasmodes]

<a href=showthread.php?s=&postid=9197326#post9197326 target=_blank>Originally posted</a> by speckled trout
...and several barnacle blennies I caught off an oil platform who love anything green.

Ohhhh I am so jealous. I love those blennies and don't have the resources or time to go get them myself. I wish they were available for sale somewhere. Please post a pic of your blennies!

Also, I really like the pics of your tank showing your DIY rock. Please, everyone else who has made their own rock post pics of what it looks like now in your tank!

Finally, I was thinking the other day of making a large structure for a corner with an overhang perhaps by making a large mold, pouring in layers of DIY rock and letting them dry in the large mold, each layer separated by something to prevent them from bonding together. Someone posted pics of doing something like this without an external mold so that the pieces fit together like puzzle pieces and I thought it was a terrific idea. You can create caves this way too I think. Also, making large structures out of smaller pieces (puzzle style) would mean less kuring time per piece too I guess.

 

[GuySmilie]

<a href=showthread.php?s=&postid=9224126#post9224126 target=_blank>Originally posted</a> by Hypsoblennius

-snip-

Finally, I was thinking the other day of making a large structure for a corner with an overhang perhaps by making a large mold, pouring in layers of DIY rock and letting them dry in the large mold, each layer separated by something to prevent them from bonding together. Someone posted pics of doing something like this without an external mold so that the pieces fit together like puzzle pieces and I thought it was a terrific idea. You can create caves this way too I think. Also, making large structures out of smaller pieces (puzzle style) would mean less kuring time per piece too I guess.

Look into using something like Visqueen vapor barrier. The clear polyethylene stuff painters use for dropcloths. You'd want to use a thickness that wasn't too stiff or it wouldn't conform to the previous surface very well.

If you use something too thin it will probably disintegrate from the caustic cement. I'd try something about 1 - 2 mils thick or so and see how that works.
Guy

 

[Rhodophyta]

I've just used damp sand or damp gravel. Bury the bottom pieces, then leave a few contact spots with a thin sand layer. Build up the next layer of rocks, creating gaps or caves between the pieces by filling spaces with damp sand. If you use plastic, it may stick. Wax paper will peel off, leaving a trace of wax or nothing at all. The sand if you use it, just becomes part of the rock.

 

[GuySmilie]

Yeah, a sand barrier would be a good idea too if the piece wasn't too complicated, shapewise.
Guy

 

[Rhodophyta]

<a href=showthread.php?s=&postid=9228099#post9228099 target=_blank>Originally posted</a> by GuySmilie
Yeah, a sand barrier would be a good idea too if the piece wasn't too complicated, shapewise.
Guy

I have some very complicated pieces made with a sand mold. You can get fine detail if you moisten the sand with molasses instead of water. If you don't want the sand to bond to the piece, grind up a handful of dry oatmeal or just use flour. Mixed in to the sand, it forms a coating on the grains that release them after the concrete sets.

 

[frank1234]

Good idea about the sand barrier. I have done the same with my setup and it worked perfectly.

 

[Nammy]

I don't have any projects on the go these day, I've just finished reading the entire Thread, and my wife will be gone for a week, I think I should make some rocks this weekend.

 

[RandyStacyE]

Anyone have any ideas as to what materials could be used instead of aragonite/reef sand in the mix.

Something super absorbent/porous, reef safe of course and ultimately cheap.

I don't live anywhere near the ocean (for sand) and I'm not going to buy bags of aragonite from my local FS if I can keep from it.

I saw a bag of kitty liter, grabbed a hand full and placed it in a cup of water. It's just clay ... so it instantly deteriorated. How about floor dry/oil dry? I don’t know.

Then it hit me … what about using vermiculite. It’s extremely absorbent, natural, very light and cheap.

TYPICAL PHYSICAL PROPERTIES
Color ----- Gold-Brown
Free Moisture, Maximum ----- 0.5%
pH (of water slurry) ----- 7.0-9.5
Specific Gravity ----- 2.5
Expanded Bulk Density (normal) ----- 4-10 lb/ft3
Mesh Sizes (normal) ----- 2-40 mesh and finer
Fusion Point ----- 2200-2400F
Specific Heat ----- 1.08 kJ/kg.K
Thermal Conductivity ----- .27-.41 BTU.in/h.ft2.F

Are their any natural and readily available types of ground up stone that could be used that you guys know of?

 

[Fishboy1230]

Does it float or is it sandy?

 

[RandyStacyE]

I believe it does float. People use it to create a floor or base for many liner swimming pools. There are a million other uses for it too. It's almost squishy kind of like cork. Vermiculite doesn't appear to disintegrate even in long term presence of water/moisture.

 

[Travis L. Stevens]

What is the chemical compound and what end effect does it have after reacting with seawater?

 

[RandyStacyE]

I started reading this page:
http://www.mineralszone.com/minerals/vermiculite.html

Vermiculite is (Mg,Fe++,Al)3(Al,Si)4O10(OH)2·4(H2O) ... whatever that is.

"chemical composition varies widely consisting of a complex hydrated aluminium, magnesium silicate and hence the analysis of the mineral is of little use in determining the vermiculite for commercial utility"

This page does show it's composition:
http://mmtclimited.org/vermi.html

I'm not sure about it's comptibility with our tanks though.

 

[hahnmeister]

Why not just use southdown?

 

[RandyStacyE]

Sounds good, but I don't think anyone has it around here. I'll look into it.

 

[Insane Reefer]

<a href=showthread.php?s=&postid=9202185#post9202185 target=_blank>Originally posted</a> by jjoos99
I made up some using some of the smaller white water softener salt and it also crumbled apart...

Anything smaller than the course solar salt crystals ends up wearing away as you mix it in, and retards the curing process dramatically, IME.

 

[Insane Reefer]

<a href=showthread.php?s=&postid=9221249#post9221249 target=_blank>Originally posted</a> by ARIANNA
... At this time I began adding vinegar to lower the pH daily. 6 gallons of vinegar and 2 weeks later I was looking for a better solution...

Yeah, it doesn't work, just looks like it does for a while.

Air/Co2 is the way to go. That and lots of water volume/movement...

 

[Insane Reefer]

<a href=showthread.php?s=&postid=9227059#post9227059 target=_blank>Originally posted</a> by GuySmilie
..If you use something too thin it will probably disintegrate from the caustic cement. I'd try something about 1 - 2 mils thick or so and see how that works.
Guy

Actually, anything plactic will work; I've used everything from plastic wrap, Glad brand bags to the bag the salt came in.

Cement won't eat the plastic....
But my cat will, lol...

 

[Insane Reefer]

<a href=showthread.php?s=&postid=9233351#post9233351 target=_blank>Originally posted</a> by hahnmeister
Why not just use southdown?

Southdown/Old Castle, etc does not exist for most of the US. Believe me, I just spent a week looking for it and it seems if I want any, I have to go to PA or NJ or CA.

 

[Insane Reefer]

<a href=showthread.php?s=&postid=9229093#post9229093 target=_blank>Originally posted</a> by Rhodophyta
I have some very complicated pieces made with a sand mold. You can get fine detail if you moisten the sand with molasses instead of water. If you don't want the sand to bond to the piece, grind up a handful of dry oatmeal or just use flour. Mixed in to the sand, it forms a coating on the grains that release them after the concrete sets.

Great Idea Rhody! That's the sort of stuff I like to read

 

[Insane Reefer]

<a href=showthread.php?s=&postid=9232049#post9232049 target=_blank>Originally posted</a> by RandyStacyE
Anyone have any ideas as to what materials could be used instead of aragonite/reef sand in the mix.

Oyster Shell. Dolomite gravel/chips. Limestone sand. Toys R Us Play sand.

… what about using vermiculite. It’s extremely absorbent, natural, very light and cheap.

I thought about it, and Perlite too, but decided that the traditional stuff would be best. OS is $9 a 50lbs bag - cheap and natural.