The Ultimate DIY Rocks!

[mr.wilson]

<a href=showthread.php?s=&postid=10425693#post10425693 target=_blank>Originally posted</a> by Yinepu
Thanks for that info Mr. Wilson! (made a note of the names). I'll be at Home Depot next week so I'll see what they have. Do you add an aggregate to your mix?

50/50 cement mix and crushed oyster shell. I get the oyster shell from a farm co-op, sold as chicken grit calcium supplement. It gives a uniform grey colour.

I find aragonite to be too white, giving it a speckled look. Aragonite is also much more expensive.

Oyster shell has the best pore matrix for molecular absorption of silicate, phosphate and many organics. Oyster shell is used as a water treatment media in many industries. It has the same PH solubility as aragonite, so it's the perfect media for the job.

 

[Yinepu]

<a href=showthread.php?s=&postid=10426014#post10426014 target=_blank>Originally posted</a> by mr.wilson
50/50 cement mix and crushed oyster shell. I get the oyster shell from a farm co-op, sold as chicken grit calcium supplement. It gives a uniform grey colour.

I find aragonite to be too white, giving it a speckled look. Aragonite is also much more expensive.

Oyster shell has the best pore matrix for molecular absorption of silicate, phosphate and many organics. Oyster shell is used as a water treatment media in many industries. It has the same PH solubility as aragonite, so it's the perfect media for the job.

Thanks again! I have oyster shell here already!

 

[Neptune777]

<a href=showthread.php?s=&postid=10426014#post10426014 target=_blank>Originally posted</a> by mr.wilson
50/50 cement mix and crushed oyster shell. I get the oyster shell from a farm co-op, sold as chicken grit calcium supplement. It gives a uniform grey colour.

I find aragonite to be too white, giving it a speckled look. Aragonite is also much more expensive.

Oyster shell has the best pore matrix for molecular absorption of silicate, phosphate and many organics. Oyster shell is used as a water treatment media in many industries. It has the same PH solubility as aragonite, so it's the perfect media for the job.

Ever get PO4 issues from the OS? I bought a few bags and did a PO4 test on some in DI water and it regestered pretty high. Is your OS pretty dusty/dirty out of the bag?

 

[mr.wilson]

<a href=showthread.php?s=&postid=10426485#post10426485 target=_blank>Originally posted</a> by Neptune777
Ever get PO4 issues from the OS? I bought a few bags and did a PO4 test on some in DI water and it regestered pretty high. Is your OS pretty dusty/dirty out of the bag?

I've never tested the crushed oyster shell right out of the bag, but I test the tank over the weeks and months it matures. I haven't measured any significant levels of phosphate.

Yes it contains fine shell (dust) from the crushing process. I don't bother sifting it out, as it binds well with the cement mix. The fine granules will dissolve (calcium carbonate) in the water more readily, but they are mostly buried in the concrete mix.

Phosphate content will range from region to region. I haven't had nuisance algae issues, so I haven't done further testing.

 

[Insane Reefer]

:sad2:
One of the floating reefs, isn't

Today I came down and the one with marbles in it had sank.

Since Mr. Wilson is so against the perlcrete, I messed with this piece. I stood on it, and bounced and nothing happened, so got a hammer. Took 3 swings to bust it. I then took the smallest fragments - pea sized to pinhead sized and dropped those in water to see what they might do. They sank. FWIW, I haven't noticed any of the bits that have shed, floating around or anything - they all pretty much sink, or in the worst case, are light enough to swirl around in a current at the bottom of a bucket.

Floating shed was a small concern for me, but I have laid it to rest.

 

[mr.wilson]

Good to hear, nobody wants flotsam in their tank, or jetsam for that matter.

I guess the portland weighs it down.

I'm not adamantly against perlite, I just don't see any benefit other than cost. The drawbacks are very minor.

 

[Insane Reefer]

Actually it was the marbles that pulled it down - the other is still floating.

Next idea would be to use something buoyant instead of a weight - I'm thinking like those little "bubbles" that kiddy toys from quarter machines come in - sealing that with silicone so it won't take on water should keep them floating...

 

[mr.wilson]

<a href=showthread.php?s=&postid=10429701#post10429701 target=_blank>Originally posted</a> by Insane Reefer
Actually it was the marbles that pulled it down - the other is still floating.

Next idea would be to use something buoyant instead of a weight - I'm thinking like those little "bubbles" that kiddy toys from quarter machines come in - sealing that with silicone so it won't take on water should keep them floating...

Styrofoam will also work.

 

[Insane Reefer]

Oooo!
Good idea

 

[medic29]

The large pressure cooker arrived yesterday. I'm thinking maybe Tuesday I may have to make a small test batch of rock and let it set until Thursday, then it will be time to "pressure" cook for ~5 hrs or so. After that, I'll boil them for the salt release.

I was watching a show on the Science channel last night and they were making large cement/concrete "drainage" pipes. They said the pipes had to be strong enough to last 100 years. Anyway, after they cast the pipe they put it in an oven with 100% humidity @ 180 degrees for like 6 hrs for it to cure; they related it to putting it in a sauna. I thought that was interesting since it is similar to what we were looking at doing.

 

[Insane Reefer]

Awesome - I love the science channel, and that is exactly what we are trying to do. Unfortunately, at 180-225°F, you can't produce (enough) steam in the oven

How about a picture of the cooker, with something like a soda bottle for scale?

 

[medic29]

I was thinking about that and going back to a thought from a while back, wondering if we were to use an older metal box or insulated cabinet of some sort, have some shelves in it to but the rock on, then a propane burner with a metal heat exchanger over it that we could constantly drip some water on it to make steam that would rise. The burner would have to be outside the cabinet and possibly the heat exchanger the bottom of the cabinet. If the burner were inside the cabinet, the steam would put out the flame.

Anyway, maybe that will be a project down the road if I can find the right items to use. For now, I'll try the pressure cooker.

 

[Yinepu]

Hey IR,
You're not going to bake the ones with the plastic bubbles or styrofoam are you?

Lol at least I hope you aren't!

 

[Salty Brother]

well i just started my first batch of LR. I made about 100 pounds or so yeterday, but i still have about two more batches cause my brother is starting a 180 and hes giving me his old 75, so we both need plenty more LR. Lets see, I used protland type 1 cement, OS, and morton water softener salt. The OS is for texture and the salt is to make the rock more porus when it dissolves. Its also pretty cool cause you can basically make any shape you want. About half the batch is still sitting outside finishing the first step of curing. Then the second half is in my ultimate curing tank. Which consits of a 150gal cow tank, a high flow sump pump (both found in my back yard, ya thats weird) and a heater. Ill try to get some pics soon, its looking like it could be succesful (knock on wood )
Alright Ill add some later.

 

[Insane Reefer]

Hey Rick, I have been brain storming an idea like that for the last few weeks. Since high heat isn't really needed, beyond getting the water to a temp that it can readily produce the required steam, I'm looking at stripping a hot plate or those little counter top electric burners college kids use in the dorms.

I think I can rig a contraption from a barrel that will have a heavy corrugated aluminum pan (used to feed livestock - purchase at feed store) of a size pretty close to the interior diameter of the barrel. Either welding or just old fashioned bolts could be used to secure it in, install the electric elements underneath that, add a temp probe and control knob, and it should be good to go.
As a fancy extra, I would stand this upright, and have a full length door cut out so I can easily load and unload rock...

Anyone see anything wrong with this?

Yin
I don't bake everything, lol - some projects just can't be baked.


Interestingly enough, the floating reefs went through nothing kure-wise. I had sort of forgotten about them, and found them when I was cleaning my rock station in the garage. I'll have to look back through the thread to see when I cast them, but I'm thinking it was about 3 weeks ago. They just sat around for that long. Then I threw them in the jar to see if they floated, they did (one sank), and so I left the remaining, floating one in the jar for pH tests and to see if it too was going to sink. It has been in the jar for 48 hours and the pH is reading 8.5
I thought this was interesting. We will see what the next 24 hours brings, but if the pH stays stable, then with no special treatment, not even kuring, this rock is ready.

Welcome to the thread, Bro'! Sounds like you and your brother have a lot of rock to make, lol, and sounds like you have a plan. Let us know how it goes, and please do post pic's! If you have questions, ask - someone will probably be able to help

 

[Insane Reefer]

Eshook.
Have you had a chance to pester your kin-folk about cement yet?

In a few days, I'm hoping, I will have some interesting reading from a gentleman over in england. He is the director of a cement testing facility and I believe holds a PhD in something cementious.
I had sent off a batch of emails at the beginning of June to as many cement places online that I could find - places like Cement.org and others. I received one reply from all of those emails, and it was just a "sorry, we can't help" type email.

Then, going back through my gmail, looking for an email I never received, I found that I did get another reply. The reply did not amuse me in the least. Seems this gentleman thought that the long email I sent him was a "wind-up" - a joke by one of his academic colleges, and he replied with that assumption in mind.
Needless to say, I sent back a snarky email telling him how not amused I was. I was totally blown away when the very next day I received a very, very apologetic email and a promise to help in anyway he can. He is using the weekend to contemplate my email and come back with a reply, so by Monday or Tuesday I am hoping to have some answers.

Some of my questions are about things "we have covered" in the threads' dark past; I wanted verification on some of the things we have accepted as truths. A few were questions I wanted further clarification on, and a few are "How can we do this better" questions. When I receive his reply, I will post all of the emails that are connected, in order, so you may read them too.

Hopefully none of you will have tears streaming down your face when you read his first reply, like my dear, loving husband did when I read it to him. After he stopped laughing, he turned to me with a mortified look and said, "That's horrible!" - and then busted up laughing again...

 

[bigtex52]

MR. WILSON,

You say that the Kwikrete Hydraulic Water Stop works well, but according to the product circular, it set in 3 to 5 minutes. How do you get enough working time out of it to get your project done. Do you do a lot of very small batches?

Ted

 

[bigtex52]

TTT

 

[Insane Reefer]

Bigtex,
While you wait for Mr Wilson to reply, you can check out this thread: http://reefcentral.com/forums/showthread.php?s=&threadid=993625
The title is misleading, but it is full of Mr Wilsony goodness

 

[mr.wilson]

<a href=showthread.php?s=&postid=10434295#post10434295 target=_blank>Originally posted</a> by bigtex
MR. WILSON,

You say that the Kwikrete Hydraulic Water Stop works well, but according to the product circular, it set in 3 to 5 minutes. How do you get enough working time out of it to get your project done. Do you do a lot of very small batches?

Ted

Yes, many small batches that overlap an inch to make up for shrinkage.

On the up side, the short work time forces me to get the job done quick. Most of your time is spent mixing cement and washing containers.

Try to find a product with a 20 minute work time. I use Bomix Swift Patch, which I now realize is only available in Canada. It's weird when you do a Google search (Bomix) and see your name in the first listing. It's nice to know my opinion ranks higher than the company website.

Thora "Thorite" (however I heard the name has changed), or Quikrete "Quikwall" will work the same. It's just a matter of availability for me.

For small projects and personal use, I would pay the extra money for fast setting cement. It cuts down on curing time and the labor involved in quickening the process. It also gives you a more malleable material that holds it's form until it sets.

For commercial production, regular portland is ideal. Rocks can be formed and stored for a month before shipping. The rocks can also cure while on the retail shelf.

My intension is to make rocks, then place them in large greenhouse vats (with live rock) for six months. This will yield a commercial supply of mariculture rock without damage to natural reefs. The greenhouse is coming this fall, but production is at least a year away.