The Ultimate DIY Rocks!

[Insane Reefer]

Thanks for the PM Rick.
Yes, you answered my questions
I had to PM Rick to see if the first batch he had made had only been done in an air kure or if it had been water kured, since he missed both times I asked for clarification
lol
For those following the "Air Kuring", his was water kured...

 

[Barto]

<a href=showthread.php?s=&postid=10111864#post10111864 target=_blank>Originally posted</a> by Insane Reefer
I am playing "Betty Crocker"

IR: Great new avatar

To All:
I hope that differences of opinion can be kept civil, for the good of the project.
This is one of the most informative threads I've followed along with and participated in (only a little participation)
Exploring different methods & possibilities has opened up several trains of thought that were not there a year ago.
I'd hate to see it jump off the track

my .02

Thanks

 

[sunkool]

Its Betty Rocker Not Crocker.

 

[Insane Reefer]

Ah, so it is.
My mind must have glossed over it as another of your grammar, spelling or punctuation mistakes.
I apologize for overlooking that...

I'll keep "Betty Crocker" for a while - I've gotten quite a few compliments on it already

Thanks

 

[sunkool]

First with the name calling now this. Like your posts are perfect.
You must have no life outside of rock making.

Truthfully, I hate to be a party pooper. I have really learned alot about cement, don't get me wrong. Thanks for all that contributed. But I really think that we are reading way too much into this. Unless you plan on sitting a house on top of your new DIY Rocks, what is the point of proper curing for strength? As long as you aren't critically jeopordizing the rock's integral strength, it should be fine. After all, only the largest tanks would need that when one rock has over 500lbs of other rock on it. The salt molding seems to be a perfect method for me so far. It became solid just as quick as any other rock that I've done. We have to remember this rock is going into aquariums that are most likely 250g or less. Even with 2lbs/gallon, there will be no one rock with over 500lbs on top of it. Heck, the average aquarium is a 75g. Once again, no one rock will have over 150lbs on it.

said by Travis L. Stevens on page 9 Here a year ago and you keep going on and on and on.

 

[onnenmd]

Can't we all just get along? This post has been going on so long because new people like me join up and ask lots of questions and everyone gets new ideas!!!

 

[Insane Reefer]

Ok.
I think I have figured out why the low temp bakes aren't working. It was bothering me as everything I've read says I should be wrong - low temps are supposed to be the correct method, so I really want to know why it seemed to go the other way for me.

I tried another batch this weekend, and had the same results - brittle, friable rock. But this time I paid attention to the bake. And I think I know why the low temps are failing.

Hardly any water had evaporated from the water pan. At 200°F-225°F, the oven isn't hot enough to generate enough steam to keep the rock moist - it quickly is loosing the pore water and the hydration phase fails.
So I did some more reading and found that in low temp ovens/kilns, steam is often produced outside the oven and is pumped in.

That solar kiln that someone mentioned a while back is looking better and better to me. A very simple boiler could be rigged to work with an outdoor low temp kiln. Not for everyone, but something to think about for some of us...

 

[medic29]

<a href=showthread.php?s=&postid=10001793#post10001793 target=_blank>Originally posted</a> by medic29
This is what they looked like after I got done making them.

Above is what my rocks looked like after I casted them. I don't have any recent pictures, but in a couple of days I plan to take the rocks out and take some more pics of them.

<a href=showthread.php?s=&postid=10004955#post10004955 target=_blank>Originally posted</a> by medic29
InsaneReefer I did make a batch of DIY rock in the past which is okay. I think I made it back in November. Here is a pic of it.

Both of these have a pH of 11 after soaking in a bucket of fresh water for a couple of weeks.

 

[Insane Reefer]

Rick. Just to make sure I'm on the same page, the rocks in the bottom picture are from the fall, correct? So maybe 6 months or so old? And these went though a mostly normal water kure, and then just sat around until a week or so ago when you threw them back into water to test them? If any of this is incorrect, please fill in what I have mistaken.

Did these older rocks sit in water or sit out dry since you stopped doing the water changes?

I'm amazed that rock of that age still has that high of a pH (11+). Even without a water change, sitting dry, the pH should have come down more than that in 6 months - the air kure test pieces that a few of us have tried have all been tried on much younger rock then that, and most where in the 10 range when tested, if I am remembering correctly.

Anyone have any idea's on this older rock?

I'm waiting to hear from the other lab monkey (who is still in the experiment, I think), his rock should be just about ready for the 2 week test. We will compare notes for the Jiffy Rock when he checks in and see if his rock fared better then yours before we try to come up with theories on why yours is still so high.

 

[medic29]

Yes, the bottom pic is the older rock. Everything else is pretty much correct.

 

[Insane Reefer]

Cool.
And did the older rock sit in water the whole time, or when you "finished" the kure did you let it sit dry, Rick?

 

[medic29]

It mainly sat in water with the exception of a couple of weeks that it sat out on a table in the sun. Then I put it back in the water to see what the pH was 2 weeks ago.

 

[Insane Reefer]

Well that blew my idea, lol.

Sorry if it sounded like I was bombarding you with questions, but often the answer can be found in the details...

Another question
I see you live in IL. The mid-west had a particularly cold winter. Did these rocks sit in temps of lower than 50°F during this winter?
Low temps can affect regular portlands cure, through I am not sure how that might apply here, if that were the case.

 

[medic29]

Yep, they sat outside in a container of water all winter.

 

[Insane Reefer]

Hmmm.
If one was lower than the other, I'd question the sand, but two different sands equaled almost the same results.
My genetics friend is over, and I posed this to him.
He suggested something that sounds far-fetched, but a google search quickly showed that it has some merit.

This is the idea. Most of us in the mid-west sit on limestone aquifers, that our local water companies tap for use. In some area's, the limestone is 'infested' (for lack of a better term) by types of bacteria that feed on something in the stone, there-by breaking it down. These bacteria often leave behind a sulfur-like smell. Some people may be familiar with a sulfur smell and orange stains from their local water - this can be from either rust in the water or these bacteria.

Far-fetched as it sounds, bacteria like these do eat cement - it might be possible that your local water is contaminated with one of these types of bacteria. Your friend at the university might be able to test the local water you use, and the limestone you are using as well as the rocks themselves, or at least the solution they have been sitting in. See if there are a lot of bacteria present, and if so, try to identify it.

This is one article I found about cement eating bacteria:
http://aem.asm.org/cgi/reprint/70/10/6031.pdf

 

[Yinepu]

Hey Insane... what was the final assessment on adding vinegar to the kure water?... did it actually help lower the ph of the rock?.. or was it just a temp fix that didn't make any difference in the long run?..

 

[BOKER420]

IR,
I'm not sure if my pH is stable, but after a double 2 hr bake at 425. Then 3 overnight heated soaks to get the salt out. And now the last batch of heated water was left for 3 days and so far the pH reads 7.

 

[Insane Reefer]

Yin, we are still trying to determine that, lol.
EAJ hasn't checked in for the two week test yet.
Medic still has really high (11+) pH, but he has that problem with older rock he made too, so I'm wondering if we aren't dealing with some odd issue with his materials or local water or something.
Boker just checked in but it will be another week and a half or so before the two week test for his rock. Right Boker?
And I have completed my last cycle of tests. My tests at two weeks are fairly consistent. Most rock after 2 weeks seems to be holding stable (or with only a slight tendency to rise a tiny bit) for the two week test period. The average range I've been hitting has been 9. I've had 2 pieces in the 8 range, and I have had 6 pieces that were in the 10 range. I have done a total of 21 pieces of rock during these last few weeks (not counting failed, low heat bakes) - the last test pieces got taken out this weekend.
I did start another batch made with CO2 water, but that is yet to start testing.

To answer your question Yin, I think that if the rock is done hydrating, or close to it, the acid will clean the rock out quicker than water alone will. It might be something to try with air kured rocks - 3 days in weak vinegar after a full 28 day cure might just do the trick.
But if your rock hasn't finished the hydration phase or come close, I think it would be sort of pointless.

I'm going to try a few batches of boiled rock next - see if that makes any difference and trying to think of other things to try as well.

 

[medic29]

IR - I had a few thoughts....1) In reference to the bacteria - first the oven baking should have killed the bacteria and/or the multiple boiling sessions; I would think either or both of these would have taken care of killing any protein based bacteria unless it was some sort of encapsulated bacteria, but then it would have to come out of the encapsulated protection to start breaking down the cement. 2) Would there be any use of re-baking these rocks at 400-450 degrees? I'm wondering if maybe it has not finished with the bonding you have discussed in the past and maybe it just didn't bake long enough. I don't know what is up with my original batch I made several months ago. I guess it could possibly be the cement I am using, but this high pH is driving me nuts (thus the reason I originally asked about using diluted muratic acid to lower the pH of the soaking water).

Any ideas...

 

[obarrera]

Is there a way to make some rock like this?

I think I read somewhere earlier in this thread that it's called ceramic rock, how do they do this rocks, I really like the shapes, looks natural.