The Ultimate DIY Rocks!

[Insane Reefer]

<a href=showthread.php?s=&postid=12168017#post12168017 target=_blank>Originally posted</a> by leebo_28
wouldn't rock candy have the same effect as the salt crystals?...maybe not dissolve as fast but still isn't as damaging to the concete. Do they even make it anyore?

Actually, research results (in real labs) indicate that sugar not only quickens the rate of cement paste hydration (after an initial set retardation), it alters the micro-structure of calcium-silicate-hydrate (C-S-H) as well. Sugar addition increased the surface area and altered the pore size distribution of cement pastes.

http://www.candydirect.com/bulk/Rock-Candy-Crystals-White-Small.html

Really expensive, but might be worth it for those wanting the extra voids...

 

[leebo_28]

say who di wha where?

 

[leebo_28]

5 dollars a pound huh , I might as well buy the live rock eh.
I did just buy the white portland and the salt crystals , so I will be making my first batch tomorrow. Trying to talk my father-in-law to give me his new 55 gallon drum to make a sauna with, deaf ears so far...

 

[Insane Reefer]

<a href=showthread.php?s=&postid=12168384#post12168384 target=_blank>Originally posted</a> by leebo_28
5 dollars a pound huh , I might as well buy the live rock eh.

Depends on what you are going for. If you are making Salt Rock, then yes, the price is outrageous (though with a little looking I found it as low as $18/5#).
If, however, a person just wanted to add a bit of void to a more traditional mud, then this should stretch out to make maybe 50-75lbs of rock.

I did just buy the white portland and the salt crystals , so I will be making my first batch tomorrow.

Groovy Let us know how it goes.

Trying to talk my father-in-law to give me his new 55 gallon drum to make a sauna with, deaf ears so far...

Tell him I said to "Give it up for the cause!" :bounce3:

Seriously, you can get recycled drums at your local recycling center - they are usually happy to sell them for $10-$20 each. Make sure that you get one that had food products in it, not industrial chemicals. Or you can get used coolers at someplace like Salvation Army or Goodwill, or a flea market...

 

[WHAT IT IS]

Nice catch on the pigs blood. I was sure that we were taught in school that it was the Egyptians...but schooling was a long time ago.

What about good ol' fashioned "pop rocks" candy?! Not sure how fast it would "pop" when mixed into the slurry...or if used as a mold....BUT would be fun to watch it!

I have only made one small batch of rocks. They are in garbage bags with moistened paper towel right now...only been 48 hours. Not sure if I have the right ingredients.

Should the cement be JUST the powder? Or should it have aggregate (sand/gravel) already premixed into the bag?

My bag of crushed oyster shells has alot of large "flakes" that measure >10mm in size. Can that be used as the aggregate or just for the mold? Should I "pulverize" it to make it into smaller flakes...say 5mm size?

At what point should I remove the rocks from the garbage bags with paper towel, and set them out to cure?

I need to get on this project ASAP. We just set-up our first reef tank 3 weeks ago in a 55g...and (as of today) were offered a free 90g w:rollface: :eek1: ...SOOOO I need to get the show on the road!!!

 

[Insane Reefer]

Sounds like you have a lot of work ahead of you, WHAT IT IS How much rock are you going to make? Something like 175-200lbs (80-90kg)?

I'm not sure about the pop rocks either (I'd think they'd just make a mess though), but you're right - it might be fun to watch

Cement is just the powder; concrete has sand and gravel. Technically, what we make our rock from is concrete (unless all you used was salt and cement - then I guess cement still works).

If you can, leave the rocks alone, in the damp (sealed bag, etc) for a full 28 days, then just put the rock outside if you are going for an air-kure (to shorten the water-kure) of 1 month or more - once they've sat for a month or two, then start the water-kure, or put them into water and start a traditional water-kure, for as long as it takes.

I typically use the shell as is. In construction, they use aggregate that is much larger then that, and I think the random size of the shell helps with adding natural voids in the matrix. If they bother you, pick out the largest pieces and use them on the surface as detail...

Be sure to take some pictures and let us know how it goes.

 

[goldmaniac]

the ratio that i like that I've found to be very strong ( i can stand on bridge pieces without breaking them)

1:1:2

portland cementld refugium sand:salt

very strong and very pourus.

as for strengthing this stuff with reinforcements, how about this idea: while watching tv or something, cut nylon window screen into 1-inch strips, or 3/4-inch strips, and then cutting the strips across the ends every 1/8th or 1/4 inch, resulting in pieces/bits of nylon screen that's approximately 1" x 1/4", and then tossing it into the cement slurry and stirring? random pieces would strengthen in every direction. Just a thought. you could cut off any nylon that ends up sticking out of the rock, and i bet it'd be quite unnoticable, anyway.

 

[goldmaniac]

ha smilies kicked in
ratio:

1 : 1 : 2
portland cement : old refugium sand : salt

 

[Insane Reefer]

I thought you were just embarrassed to be recycling sand...
LOL

Actually, I was thinking last night before sleep claimed me. Would doing what you are saying with monofilament work? How well does monofilament hold up in saltwater?

 

[logiktest]

About using monofilament... If it's Dyneema, it can resist corrosive chemicals. It's an ultra high molecular weight polyethylene (UHMWPE), commonly known as high-performance polyethylene (HPPE). Thank wikipedia for that little tidbit.

 

[leebo_28]

:eek2: A quick question...My father-in-law just routed some aluminum over my open bag of sand...I caught it quickly but their are some little shavings still in the bag...I can't sift it out, do I need to just buy another bag :mad2:

 

[goldmaniac]

I think the monofilament would hold up fine in salt water, since they make fishing line out of it, I believe. Or at least they used to..

but I'm not sure that monofilament has anything that the cement can hold onto. here's what I'm picturing:

gross analogy, I warn:

pulling a single thread or a hair out of a bowl of jello probably wouldn't be too hard and wouldn't resist too much. It'd probably slide right out, at least some of the time. but get a knot of multiple threads or hair (gross), and the jello would have something to grab onto and pulling the clump of thread or hair out would proabably tear out of the jello, instead of letting it slide out.

That's what I'm picturing the difference between monofilament and window screen. the criss-crossing of the nylon screen would grab and set into the cement much more, i'm guessing.

But my nylon screen idea might go out the window (heh heh) if the nylon screening stretches, as I'd picture these tiny pieces doing. if it stretches, there's no strength.

maybe ... back to the pvc shavings? I think originally they were used for coralling growth, right? but they'd be firm enough to work.

But I think using the crushed oyster shell would do the job better than anything plastic. and that idea has been out for a while.

AKA diatomateous (sp?) earth, right?

maybe using sand AND crushed oyster shell would create a very strong bond... just speculation. this is the brainstorming that creates these great recipes. I used both sand and crushed oyster shell on one of my batches, came out well. never did a strength test, though.

 

[goldmaniac]

I'd get another bag of sand and make the father-in-law pay for it.

tell us how that goes....heh heh

either way, i'd say the sand is unusable. not worth the risk, IMO.

 

[Insane Reefer]

Hey Guys

First, the important question:
Leebo, it is fine, so long as we are talking just a bit. The cement is made with alumina, so that extra little bit will probably be harmless.
On the upside, if the filings are tiny enough, they might react with the cement and cause little voids Aluminum powder is something that can be added to create voids, but it is really hazardous stuff - can blow up for next to no reason and is really bad to breathe...

Monofilament. Thanks for the info Logik If I decide to try this, I will keep an eye out for something along those lines..

Goldman - thread like fiber has been added to cement forever. Usually it was something like straw, horsehair or hemp fiber, or, as I mentioned, fiberglass. All slim thread like structures. You put enough of these threads in, and it is supposed to make a difference.
And remember we had that one guy, that posted, that knows the GARF crew. GARF stopped using shavings because, over time, the shavings ended up degrading and we don't want that.
And sweetie? What you are talking about with the OS is already one of the "recipes": Ol' Skool & Ol' Skool+ are a blend of sand and either crushed oyster shell or crushed coral, and more recently, perlite. Cement is the glue, but you really should give it something to glue together. Cement without aggregate (at least sand) has very little long-term strength, according to the Pro's.

And diatomaceous earth consists of fossilized remains of diatoms, not oyster shell...

 

[WHAT IT IS]

<a href=showthread.php?s=&postid=12172092#post12172092 target=_blank>Originally posted</a> by Insane Reefer
Sounds like you have a lot of work ahead of you, WHAT IT IS How much rock are you going to make? Something like 175-200lbs (80-90kg)?

I'm not sure about the pop rocks either (I'd think they'd just make a mess though), but you're right - it might be fun to watch

Cement is just the powder; concrete has sand and gravel. Technically, what we make our rock from is concrete (unless all you used was salt and cement - then I guess cement still works).

If you can, leave the rocks alone, in the damp (sealed bag, etc) for a full 28 days, then just put the rock outside if you are going for an air-kure (to shorten the water-kure) of 1 month or more - once they've sat for a month or two, then start the water-kure, or put them into water and start a traditional water-kure, for as long as it takes.

I typically use the shell as is. In construction, they use aggregate that is much larger then that, and I think the random size of the shell helps with adding natural voids in the matrix. If they bother you, pick out the largest pieces and use them on the surface as detail...

Be sure to take some pictures and let us know how it goes.

Probably (hopefully) will make at least 100 lbs... Have some ideas for "plates" as the primary structures since they are "low mass" size. From what I have read, the small stuff tends to kure faster than MASSIVE pieces. But I am still planning on making a 3 ft long double arch!:eek1: :eek1: Might take from now til xmas to kure.

 

[Insane Reefer]

It's hard to give estimates on kure time. I've made a few plates to sell, and they are popular, and for the recipe I use, and how I make them, they tend to kure out in under 2 months (once in water), at around 3-4". For that arch, you might consider 3" PVC as both a way to sort of hollow it out (kure quicker) and to give it support. PVC can be bent with heat - I use the stove top for big PVC, set the electric element to medium high and heat the pipe over that until I can bend it. I wear silicone/silicon? cooking mitts to protect my hands, and vent the kitchen when I do it. Drilling 1/4" -1/2" holes in the PVC will give the cement a place to anchor to. Done right, you could have this ready to use by mid to late summer.

 

[goldmaniac]

hey Insane, I came across a thread asking about floating reefs.. did the work on the floating "death star" ever have a happy ending? is it working?

 

[a1amap]

<a href=showthread.php?s=&postid=12173753#post12173753 target=_blank>Originally posted</a> by goldmaniac
I think the monofilament would hold up fine in salt water,

That's what I'm picturing the difference between monofilament and window screen. the criss-crossing of the nylon screen would grab and set into the cement much more, i'm guessing.

But my nylon screen idea might go out the window (heh heh) if the nylon screening stretches, as I'd picture these tiny pieces doing. if it stretches, there's no strength.

maybe ... back to the pvc shavings? I think originally they were used for coralling growth, right? but they'd be firm enough to work.

But I think using the crushed oyster shell would do the job better than anything plastic. and that idea has been out for a while.

AKA diatomateous (sp?) earth, right?

I used guttter guard as a type of rebar for my rocks. Holds up well and makes them easy to shape the long and tall rocks. PVC shvings would add strength and yes coraline would first populate the PVC.

I have wondered about diatomaceous earth but since it is mostly silca, I stayed away from it. originally from Wiki...

The typical chemical composition of diatomaceous earth is 86% silica, 5% sodium, 3% magnesium and 2% iron

 

[Rysam]

i have several rolls of fishing line from 8 lbs to 40 lbs floating around. i will cut up a bunch and see how it works. i have a roll of weed whacker line that may work too. at the very least it would make some cool tunnels.

 

[Insane Reefer]

<a href=showthread.php?s=&postid=12181252#post12181252 target=_blank>Originally posted</a> by a1amap
PVC shvings would add strength and yes coraline would first populate the PVC.

If something degrades, it isn't providing strength - at least not for the long term, and GARF stopped using it for that reason, or so we've been told. But yes, coralline does love PVC. Possibly PVC powder sprinkled on the rock when it is cast? Could finely powder the PVC shavings in a blender...

I have wondered about diatomaceous earth but since it is mostly silca, I stayed away from it. originally from Wiki...

Not the same as "free" silica, so no reason, really, not to use it.