The Ultimate DIY Rocks!

[Azazael13]

well we have no kids (just two puppies) so that wasn't the issue. One of those things were I am sure I messed up but don't realize I did something wrong ><

[Travis L. Stevens]

I honestly doubt that the pH will spike beyond what is reached in the first 48 hours of soaking. After all, if you are able to get the deepest salt out within 24 hours of soaking, then that means water has already started to flow in and out of the rock in the thickest parts. So, any Ca(OH)2 that hasn't bonded to the Silicates in the clay deep inside the rocks will definitely be able to flow out into the water and spike the vat. So, my theory stands as whatever pH you reach in the first 48 hours after curing and baking is the initial pH, and no future spike will occur.

Come to think of it, with all that heavy thinking... If it is Ca(OH)2 that is spiking the water, vinegar won't help...sort of. Vinegar allows limewater to dissolve into the water at a higher concentration. Thus, you can take more Ca(OH)2 out of the rocks per water change of the Kuring vat versus without vinegar. But it still doesn't get rid of the Ca(OH)2 until all of it is gone. So, I would like to know what chemical would neutralize or cause the Ca(OH)2 to not effect the water. Maybe that is a better source. Consider it Water Dechlorinator for DIY Rocks

[Travis L. Stevens]

Yinepu, I doubt that the fumes from baking the rocks will do anything at all beyond an unpleasent, dirt like smell. Remember, I baked my first batch of rocks. I didn't die, my wife didn't, my kids didn't, my dog didn't, none of my fish did.... I think you'll be fine.

[Azazael13]

with those birds you have to take so many precautions though. My parents had one and I got in trouble for leaving a frypan on the burner with nothing on it, because of the fumes that it could release. Those birds are super sensitive to that stuff.

[Insane Reefer]

Actually, Yin has a legit worry - birds are noted for their extreme sensitivity to fumes. You aren't even supposed to smoke cigarettes around them. I bought a $1200 vacuum that also doubled as a air purifier when I got my bird - I smoke, a lot, and didn't want to kill my bird...

I didn't realize you had tried baking too, Travis, or if I did, I had forgotten it. How were you doing it, and why did you decide it didn't work?

[Travis L. Stevens]

Yip/Insane, I forgot about the old usage of canaries and mine shafts. Sorry, not a bird person. Like cats, I like them but they don't like me.

Insane, all I was doing was letting them sit for a couple hours to harden on the outside so I could turn them over and sculpt off the flat side from them sitting on a pan. Then I would put them in the oven at 250ºF for a couple hours to harden up. I then let them cool so I could touch them and placed them in water. Nothing major had happened, and there wasn't a noticable difference. A lot of people said that this would jeopordize the strength of the cement. I didn't 100% believe it since I, a 250lb man, could stand on the rocks and shift my weight in little hops (I don't balance well to jump on it) and the rock didn't break. The actual curing still took as long as other tries. On the other hand, you are doing many things different than what I did. You're letting it Cure longer which I think has the biggest impact on getting the Ca(OH)2 to bond. Cooking it with humidity for a longer time will only speed up the process. I honestly thing that you are on to something with your current method.

Here's something I would like to try.

1) Form rocks with your prefered recipe.
2) Let the rock cure in moist conditions for 48 hours to allow C-H-S bonds to form and harden the rock for baking.
3) Bake the rock at a lower temperature (250ºF?) with LOTS of moisture for a longer time (8-12 hours) to speed up the C-H-S bonding process
4) Proceed by putting it in hot water ASAP to release the salt.
5) After salt release and water change, test water as is after 24 hours to see if any extra Ca(OH)2 has not bonded with silicates in the form of spiked pH.
6) If the pH is high, add vinegar at an unknown ratio to increase Ca(OH)2 solubility in water. Allow rock to sit for 24 hours and change the water.
7) Wait 24 hours and test pH. If pH is still high repeat steps 6-7 until pH is at a managable level.

[Insane Reefer]

Travis, I wish my rig was running
I can tell you from my reading that whatever it is causing the pH in our rocks, it is affected by acids - there are articles on the net about cement and pH contamination, and ways to lower the pH, and acids are a tried and true method. And pH is the only thing we need to worry about at this stage.
That's why I kept wondering why it never seems to work for us, and that's when I came up with the idea that we are trying to do it with green or uncured rock. Basically, everyone was trying to skip the cure so they could go straight to kuring. And that just doesn't work.
But I know the acid is working, as the same pieces caused the water to spike immediately - there is no way 1 gallon of water would drop the pH that quickly, without changes, unless the vinegar was working.

[Insane Reefer]

Ok, at 250°F I imagine all you would accomplish is drying the rock out, which would make it brittle, if no bonds had had a chance to form.
Industry standard baking temp for bricks and blocks of cement is 400°F, under pressure and with moisture, and are baked "for several hours". I think they have probably done a lot of the hard work for us - they aren't going to spend one penny more to produce their blocks than they have to, and that includes energy costs - they probably have found the best ratio of heat/moisture/time for their buck. We are disadvantaged in that most of our stoves aren't pressurized, but I think for our non-house building purposes, pressure is unnesseccary.

I think prolonged baking will have no significant impact either way - other than costing more in electricity, both for the oven and for vent fans and AC to keep the house cool. I could be wrong, so testing is in order. I would be really interested in your results, for my collected data, so keep us posted, please.

If I can get the guys out of the house for that long, I will try a batch myself, if we get a cool day soon.

[Travis L. Stevens]

Okay, here it goes. IR, it seems like your missing a piece of the equation that I know

I can tell you from my reading that whatever it is causing the pH in our rocks.....

That would be Calcium Hydroxide (Ca(OH)2). The same thing as pickling lime, kalkwasser, etc.

, it is affected by acids

Correct. It is a base, so it would be effected by an acid. The reult of a neutralization with an acid would give off Hydrogen and some form of salt

there are articles on the net about cement and pH contamination, and ways to lower the pH, and acids are a tried and true method. And pH is the only thing we need to worry about at this stage.

I agree. Thus why I'm curious what type of acid would neutralize Ca(OH)2 across the board. Theoretically, Ca(OH)2 has a pH of ~12. That's 5 points higher than Neutral. Thus, to neutralize it, we would need something 5 points lower than Neutral. Thus we would need to use something with a pH of 2. Vinegar is a 2.9, so it won't completely neutralize it. Lemon Juice has a pH of 2.4. Gastric Acid has a pH of 1.5-2 though. Anyone want to eat some rocks? In short, we need to find something eco-friendly, cheap, reef-safe, easily available with a pH sufficient enough to neutralize the extra Ca(OH)2 without actually dissolving the rock itself.

That's why I kept wondering why it never seems to work for us, and that's when I came up with the idea that we are trying to do it with green or uncured rock. Basically, everyone was trying to skip the cure so they could go straight to kuring. And that just doesn't work.

Au contraire, mon frere. What was done in the past WAS working. It was just working too soon. The strength of the rocks is determined by the C-H-S bond. When the C-H bond occurs, you get Ca(OH)2 that spikes the pH. It takes time for the C-H to bond with Silicates to make the C-S-H bond and thus the only Ca(OH)2 that is left in the rocks is the ones that weren't able to bond with the Silicates. The addition of Fly Ash is to help the extra Ca(OH)2 to bond and make the rock harder. Out purpose is not to make the rock strong though. We want it strong enough to withstand the weight of the rocks on it. Thus, we don't need the Fly Ash for extra Silicates, nor do we need a total C-H-S bond. So, what we need to do is find what is an "amount of strength that we need" versus "the time it takes to get the strengthening through C-H-S bonds done" versus "the time it takes to get rid of the extra Ca(OH)2 out of the rocks". In short, what happens when green rock was cooked immediately and then tossed in water was very little strenght/C-H-S bonds were made, so the rock was weak and it took a long time for straight water to bring out the abundant Ca(OH)2. Now that you have refined the process by allowing it to cure in a moist environment for X amount of time, and then humid baking it for Y amount of time has caused the C-S-H bonds to form much faster. The problem is still that there will be Ca(OH)2 left over (as you know).

But I know the acid is working, as the same pieces caused the water to spike immediately - there is no way 1 gallon of water would drop the pH that quickly, without changes, unless the vinegar was working.

That's true, to an extent. The pH drop was done with the Curing and Baking, not the Kuring with or without acid. The acid is neutralizing the extra Ca(OH)2, until the water reaches the saturation point. Thus, a water change will repeat the process at full strength. Essentially, the Curing and Baking increases C-H-S bonding rate, and the Kuring stops it and draws out the excess Ca(OH)2.

I hope that helps things and brings us both on page one. We're almost back to square one with how to manage to get rid of the Ca(OH)2 without harming the rock itself. What you've done is shorten the process dramatically by speeding up the C-H-S bonds. This is something Rhodophyta has been saying since before the first split. But what wasn't mentioned is the wet baking actually increases C-H-S bonds.

[Travis L. Stevens]

Ok, at 250°F I imagine all you would accomplish is drying the rock out, which would make it brittle, if no bonds had had a chance to form.

Agreed. That is without the moisture. That's what I was doing with the first batch; no moisture slow cook for drying purposes. I agree this probably made it worthless for commercial use. But with added moisture at the lower temperature, what would be the difference? I would assume that the C-H-S bonds would form faster at a higher temperature even if the humidity was the same. So, a 250º moist environment would yeild C-H-S bonds more slowly than a 400º moist environment. But, how much energy does it take to power 400º for four hours versus half the temperature for two times as long?

Industry standard baking temp for bricks and blocks of cement is 400°F, under pressure and with moisture, and are baked "for several hours". I think they have probably done a lot of the hard work for us - they aren't going to spend one penny more to produce their blocks than they have to, and that includes energy costs - they probably have found the best ratio of heat/moisture/time for their buck. We are disadvantaged in that most of our stoves aren't pressurized, but I think for our non-house building purposes, pressure is unnesseccary.

Agreed. No quarrell there.

I think prolonged baking will have no significant impact either way - other than costing more in electricity, both for the oven and for vent fans and AC to keep the house cool. I could be wrong, so testing is in order. I would be really interested in your results, for my collected data, so keep us posted, please.

That's actually not true. The longer you bake (in a stable, moist environment) would mean that more C-H-S bonds will form until you run out of Silicates for the Ca(OH)2 to bond to. Now, how long does it take for all Ca(OH)2 to bond to available silicates is still an unknown. Theoretically, there is a chance that if we knew the optimal time range for baking the rocks with moisture that the available Ca(OH)2 left in the rocks will be so minimal that there wouldn't be a Kure time at all. Granted, the Ca(OH)2 would have to be so minimal that it would need to have a pH of about 8.5-8.6. The extra .2 pH of Ca(OH)2 could just be considered supplemental dosing with limewater

Regardless, I'll still test it all out with variable until someone can find an exact time used by the cement industry. Afterall, where would the fun in it be if we quit now

If I can get the guys out of the house for that long, I will try a batch myself, if we get a cool day soon.

If you don't mind me asking, who are the guys? I'm going to do what I can to make a LARGE batch of rocks tonight, fire them at 400ºF with LOTS of water for a little more than four hours, and then drop them in hot water and proceed with your steps. Just to see if the pH is different. I'll try for 6 hours.

Travis's Half Baked Test
I need help from some people. I don't have any extra cement blocks handy, and I'm not going to buy them either. If anyone has some in a garage, would they be willing to drop it in a bucket of RO/DI water (or dechlorinated water) and test the pH in 24 hours? This should help determine how low we should be able to get our rocks through baking.

Obviously we can't beat what the cement industry does with quick curing through baking, but maybe we can get close. For example, if the pH of the block is 8.8 after 24 hours, and the pH of IR's DIY Rocks was 9.0 after 24 hours, then obviously 4 hours is about perfect for what we can do at home.

[Insane Reefer]

Originally posted by Travis L. Stevens
Okay, here it goes. IR, it seems like your missing a piece of the equation that I know

I don't have access to my notes right now - I refer to them a lot - cement and its chemistry is a vast field, and the more I ask, the more I have to search, and the more I need my notes, lol
There is something here I can't put my finger on, but until I get my notes back, I will just have to wait, or hope at 3am it pops into my head...

I agree. Thus why I'm curious what type of acid would neutralize Ca(OH)2 across the board. Theoretically, Ca(OH)2 has a pH of ~12. That's 5 points higher than Neutral. Thus, to neutralize it, we would need something 5 points lower than Neutral. Thus we would need to use something with a pH of 2.

I know I read somewhere that Sodium Bicarbonate could be used for this purpose.
This is the link - read this. http://www.miswaco.com/Products_and_...ICARBONITE.pdf
It was posted by Tahlequah several pages back, and helped spark my latest chain of thought.
I don't understand the formula though, so gave up on the idea based on not knowing enough to use it...

If you have the math and chemistry to figure it out, the formula is given in that pdf.

[Insane Reefer]

Keep in mind that a pH test taken about 6 hours after releasing the salt, and placing in clean fresh water, went up past where my test can test. In just 6 hours it made one gallon spike higher than I can test for.

The pH went to 9 after 3 days of vinegar - and I never changed the vinegar solution. It seems to be stable at 9 after 3 days of fresh water pH testing.

I think today is a dumb day for me. I will re-read all this tomorrow - maybe I can form better replies then...

[Travis L. Stevens]

I don't have access to my notes right now - I refer to them a lot - cement and its chemistry is a vast field, and the more I ask, the more I have to search, and the more I need my notes, lol
There is something here I can't put my finger on, but until I get my notes back, I will just have to wait, or hope at 3am it pops into my head...

For all intent and purposes for us DIY Rock-ers, all we really need to know is that the Calcium in the lime in the cement reacts with the water first, making Ca(OH)2. The Ca(OH)2 then reacts with the silicates in the clay to give the rock its strength. There are not enough silicates in the mix so that all Ca(OH)2 bonds, so there will always be some Kuring involved. We can either increase the Silicates and add strength to the rock by adding something silicate based (Fly Ash), but it would take a long time for ALL the Ca(OH)2 to complete the C-H-S bonds. Or we can stop the strengthening process (AKA Curing; AKA C-H-S bonding) by tossing it in water and releasing the Ca(OH)2 before it gets a chance to bond to the silicates. That's it. Kuring just takes the Ca(OH)2 out of the rocks to make it safe for the aquarium.

Now, you've done a huge step by applying cement industry techniques and speeding up the C-H-S bonds. Now we need to figure out a few things depending on the method someone chooses to make the rocks reef safe. The length of time that it takes to bake the rocks and get all the C-H-S bonds possible, what type of acid is best used to neutralize any leftover Ca(OH)2, how much acid to do such, how often the Kuring liquid needs to be changed (whether it is water, acid, or a mixture), and a few other small tidbits.

These little keys are all that is left to unlock the door for the quickest Kure time on rocks.

I know I read somewhere that Sodium Bicarbonate could be used for this purpose.
This is the link - read this. http://www.miswaco.com/Products_and...BICARBONITE.pdf
It was posted by Tahlequah several pages back, and helped spark my latest chain of thought.
I don't understand the formula though, so gave up on the idea based on not knowing enough to use it...

I don't see how Sodium Bicarbonate (Baking Soda) will help eliminate the pH problem of the rocks. Baking Soda is a base. Bases have high pH's. To neutralize the problem chemically (which is what you're trying to do, IR), you need something with a low pH; an acid. You're on the right track. The use of Baking Soda forces the Calcium out through participation. This is very similar when the Calcium is too high for the Magnesium and Alkalinity in an aquarium and you get all the calcium percipitated on pumps, heaters, etc. This isn't really a huge problem for the rocks except one thing. As the Baking Soda pushes out the Calcium, it leaves caustic Soda behind. This in turn would just be trading one problem for another. In fact, in the article itself, it says not to use it for our application (sort of )

Unless a low pH is desired, Sodium Bicarbonate should not be used to treat soluble calcium in water-base muds and makeup waters; soda ash should be used to reduce calcium and soften makeup water.

[Travis L. Stevens]

Keep in mind that a pH test taken about 6 hours after releasing the salt, and placing in clean fresh water, went up past where my test can test. In just 6 hours it made one gallon spike higher than I can test for.

The pH went to 9 after 3 days of vinegar - and I never changed the vinegar solution. It seems to be stable at 9 after 3 days of fresh water pH testing.

Oops. My misunderstanding. I thought it was 9 after the initial testing, not three days after. Regardless, I think the spike has been reached and you're now on the downward slope of safe rock. Still, your time length has been far less than most.

[Insane Reefer]

quote:
--------------------------------------------------------------------------------
Unless a low pH is desired, Sodium Bicarbonate should not be used to treat soluble calcium in water-base muds and makeup waters; soda ash should be used to reduce calcium and soften makeup water.
--------------------------------------------------------------------------------

The way I read that, SB will produce a low pH - which is what we want; use fly ash if pH doesn't matter. If I misread that, then my bad.

[Travis L. Stevens]

Whether you misread it or I misread it is gonna have to be determined by a professional

I read it as Sodium Bicarbonate will push out the Calcium with the Bicarbonate, but the Sodium (Soda after all the chemical process work out) will be left. Thus, the pH would still be high and cause the rock to be caustic enough not to be suitable for reef tanks. The Fly Ash wouldn't matter in our case unless you want to wait an incredibly long amount of time for all the Ca(OH)2 to bond with the Silicates in the Fly Ash

[Insane Reefer]

LOL
Anyway, I was a bad monkey last night and didn't cast, but I did cast today - just finished at 2pm. So my bake will be Wednesday evening, after dinner.
I made 3 test batches. 1 white cement and 1 grey cement "ol' skool+" and one grey with sand and salt only (I'm thinking of you Travis).

Batch 1 and 2, white and grey respectively used the same recipe, as follows. 1 cement, 1 sand, 1.5 CO, 0.5 CC and 1 salt.
Batch 3, grey cement and sand was as follows: 1 cement, 1 sand, 2 salt.

All 3 batches will be treated separately, but identically, and all results will be posted.

[Yinepu]

Originally posted by Travis L. Stevens
Yip/Insane, I forgot about the old usage of canaries and mine shafts. Sorry, not a bird person. Like cats, I like them but they don't like me.

Hey, it's ok.. it's just after paying $1,500 for a parrot.. you tend to be a bit cautious!

[Yinepu]

ok.. i know NOTHING about chemistry... so what I am going to ask may be the stupidist question in the world.. but instead of vinegar, could you use some of the pond/spa/swimming pool "PH down" type chemicals?

[Azazael13]

Originally posted by Yinepu
ok.. i know NOTHING about chemistry... so what I am going to ask may be the stupidist question in the world.. but instead of vinegar, could you use some of the pond/spa/swimming pool "PH down" type chemicals?

oh oh I think I can take this one!!


No, mostly because that will just lower the ph of the water, not the rock.

[Yinepu]

Originally posted by Azazael13
oh oh I think I can take this one!!


No, mostly because that will just lower the ph of the water, not the rock.

but wouldn't that have the same effect? The spa chemical we have is sodium bisulfate. After a quick google search I found this: "Solutions of sodium bisulfate are acid, with a 1M solution having pH of 1.4"

[Insane Reefer]

Whatever effects the water will effect the rock. My question wouldn't be "would it work?", but instead, "will it be safe for the reef?".

Something like that might bind to the rock, and leech into the system.

I've asked this same question several times, and never gotten a reply to it.

[Azazael13]

I fail

I thought I saw somewhere it had to do with just affecting the water and not the rock (didn't know theph level was so low on those)

[Yinepu]

Originally posted by Insane Reefer
Whatever effects the water will effect the rock. My question wouldn't be "would it work?", but instead, "will it be safe for the reef?".

Something like that might bind to the rock, and leech into the system.

I've asked this same question several times, and never gotten a reply to it.

they say it's used in pet foods... so i dunno how it would affect corals and other critters... (would the concentrations be safe basically...)

[Yinepu]

well.. i just found this:

Sodium Bisulfate directly acidifies the diet without affecting the calcium/phosphate ratio. Sodium Bisulfate Animal Feed Grade is one of the safest products available when compared to other pet food acidifiers. It is classified as a general purpose food additive under AAFCO Feed Ingredient Definition Table 87.5.

from http://www.jones-hamilton.com/produc...bi_animal.html

Sodium Bisulfate
MIXING INSTRUCTIONS: Mix 30 grams of crystals with 60 ml (2 oz) of water. Shake well, then use one drop of this stock solution per gallon of aquarium water and this will lower the pH by 0.2.

USE: To lower pH of aquarium water.

from here:
http://reefshow.com/html/modules.php...rticle&sid=245