The Ultimate DIY Rocks!

[Insane Reefer]

<a href=showthread.php?s=&postid=9997809#post9997809 target=_blank>Originally posted</a> by Travis L. Stevens
All, I tested my rocks last night and the pH of the water was off the charts, tasted salty, but showed 1.000 on my refractometer. But, my refractometer is calibrated for 1.025 seawater and not low amounts of brine. I then drained the tub and refilled it with hot water.

Yeah, I pulled the salt and sand only from my testings - I just can't get the salt out in a reasonable amount of time (for this process) - until water is flowing through it, acid will do nothing but kure the outer layer. As we have seen from my pieces, which after vinegar, tested very low in the 12 hour pH test (8.0), but the only parts getting kured are the out 1" or so - the inner rock is still packed with salt and one would have to assume at a very high pH, still...

My hubby said I could get a digital pH thingy next week! That will make testing so much easier

 

[Travis L. Stevens]

And that is why I differentiate between them - Ol' Skool+ as opposed to Ol' Skool

I always wondered why you put a + at the end of it. It just never occurred to me.

Ok. A while back we were talking about "Air Kuring", and I took a 45 day old piece that had sat out to test. I then treated it with a week or so in a vinegar solution.
First week out, pH was good - around 8.4, but over time it has risen (and I have been good about evaporation) - the test water has risen to 9.5 after a little over a month. But that was with no water changes - something others might want to look into, I'm thinking.

On a side note, the Ca(OH)2 that is coming from the rocks is most likely being broken down from lower-than-seawater pH from the freshwater it is Kuring in. In a seawater-style pH (8.2-8.4), less will come out if any, and what does come out shouldn't pose any trouble that the life in an aquarium couldn't take up and use such as hard corals.

I'm looking into a pH probe as well. We'll see though. They're a little pricey for my pocketbook.

 

[medic29]

Well, I did it. This morning I got my stuff together and make some DIY rock. It didn't take that long and actually went faster than I expected.

This is what the pulverized limestone looked like.

This is a close up of the stuff. I placed a penny for size comparison.

This is what they looked like after I got done making them.

Now my questions....
What is the minimum time they need to sit there in that tub? What is the purpose for them to sit there?

I only have tomorrow to bake them, so I was thinking about doing this around mid-morning. Will there be any ill effects if I bake them before the 24-hour period? Do I need to wait longer before baking them? Now I bake them at 400 degrees for around 4 hrs right? Then dip them in hot water several times...I was also thinking of boiling these for about an hour, then letting the water cool. After the water cools I was going to rinse the rocks some, then refill the pan, bring it to boiling again and let it boil for about an hour, then let it cool again. Then repeat this a third time.

Does anyone see a problem with this?

Now it wouldn't be for several hours before I could get them into a tub of vinegar and water solution. The rocks sit in this for 3 days, right? Then into a tub of water for a couple of weeks.

Does this sound right??

Thanks for the input.

Oh yeah, here is a link to a page on my web site in reference to this experiment.

 

[eaj43081]

just got done baking the rocks and doing a couple salt release baths and this is what I have so far for comparing the glass block mortar mix with just portland cement.

This was taken after I pulled the rocks out of the oven, the mortar mix was on the right. Just coming out of the oven I did notice that the mortar mix rock was a lot whiter but after I started soaking the rock They both seem to be the same color, again the mortar mix rock is on the right.

I dont know if baking them together somehow leached the colors together or what? On the surface I did notice more open pours on the mortar mix, probably from useing more salt in the mix, and in the salt release bath I did notice the water was a lot more cloudier than the other batch, this could also be from more salt releasing. But here is a close up of the mortar mix rock.

 

[Insane Reefer]

Hey Rick,
You only need the pieces to sit long enough that you can handle them - this usually takes around 24 hour, IME, especially if you make delicate lacy pieces. And 24 might not be long enough if you make really lacy pieces - 36 to 48 might be required.
Making rock fast doesn't matter if it all breaks before it is ready.
Use your judgement.
It sounds like you have everything in hand. You will probably need 24 hours of water changes, every 6-8 hours or so to get all the salt out, and no vinegar until you do get it out. Read the form I sent you for more details - I covered pretty much everything I could think of in that, including boiling, which would be fine, and seems to draw out a lot of the crud. Home brewers should be familiar with this - boiling removes impurities from musts, like mead, causing the junk to float to the top. It might be that with boiling you could cut the time down on the salt release to just a couple of hours. If you try it, time it so we can see what the difference is.
Good Luck!

Eaj Great Job! That mortar mix looks shiny - is this the case? Shiny could be an indication that too much water was used in the mud - did it seem like maybe it was too wet, or do you think this is just the way it behaves? Shiny would make me think that there would be little in the way of biological filtration potential, however I bet it would grow the heck out of coralline algae
I don't think you could get any leeching between the rocks, like you are describing - I would imagine that it is a coating of efflorescence - I noticed it on the grey rocks I did. It could be something else, but I wouldn't worry about it. As far as one being more cloudy than the other, well, you are using two similar but different cementious products; I would be surprised if there weren't any differences, and amount of crud produced and released would be an almost certain difference.

Rick, Eaj & Travis
Have either of you (not Travis) made rock before? If you have, how would you compare the two? What sort of thoughts did you have? Did you find the instructions fairly easy to follow? What were your thoughts on the fumes and did it leave a mess in your ovens? Did you feel at any time that you might be endangering yourself, your equipment or your animals?
Extra Credit Questions
Currently the rocks I've made are sitting at 9ish. Based on what you just did, if we never manage to get the rock below this pH with the current method as outlined, would you still use this method and then finish the last half-point of pH with traditional water changes, or would you just make it the traditional way?

Thanks guys - I appeciate your efforts as I am sure the community in general does.

And I would still like more monkeys
Email or PM me with an email addy I can send the streamlined instructions and form to if you want to jump on the bandwagon.

 

[Azazael13]

Ugh I am the middle of a full algae bloom from a set of rocks I made. How long does this normally last? My sand bed looks horrible

 

[medic29]

First batch

First batch

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.

I made this using 1 part cement, 1 part aquarium gravel, 2 parts salt. The rocks seemed really fragile, the material didn't want to stick together when I was trying to form the rocks. It took quite a while for it to dry. I've had it in water since then. They seem really porus.

And the rock is light after the water drains out of it.

The problem I have with this is the pH is still high. Now I have not been religious about the water changes with this first batch. But, I took the rocks out of the water yesterday and tested the pH and it was still over 12. I'm definitely not happy with this first batch, I can't seem to get the pH down on them.
This is one of the reasons why I wanted to try this method. I'd take a pH of 9 over the pH of 12.

Another problem I noted with the first batch is that they seem brittle. Now, I can understand some of the rough areas breaking off on the outside, but....let's just say I'm not pleased with the first batch I made. I am more excited about this batch I made yesterday.

When making this batch yesterday I could tell it was different. I was able to form the rock easier. About 8 hours later I was able to pick up some of the pieces and look at them without any problem. I plan to bake them this morning in about an hour I will start the process. I'm excited!!!

 

[Insane Reefer]

<a href=showthread.php?s=&postid=10004815#post10004815 target=_blank>Originally posted</a> by Azazael13
Ugh I am the middle of a full algae bloom from a set of rocks I made. How long does this normally last?

How old is your tank Az and how long have the rocks been in there? What sort of bloom are you getting? Are you sure you aren't going through a maturity bloom?
The algae I get from my rocks usually stays on my rocks, or really close to them.

 

[Insane Reefer]

Cool Rick - I'm baking as I write this. I'm trying a longer bake this time - see what 6 hours does for, or to, the rock.

Keep us posted

 

[Azazael13]

<a href=showthread.php?s=&postid=10005015#post10005015 target=_blank>Originally posted</a> by Insane Reefer
How old is your tank Az and how long have the rocks been in there? What sort of bloom are you getting? Are you sure you aren't going through a maturity bloom?
The algae I get from my rocks usually stays on my rocks, or really close to them.

Tank is a little over a year. I suppose it could be due to something else, but it showed up after I added the rock. The bloom is close to the rocks but is also on the sand, none on the glass though. The color of it is brown, I can try for a picture tonight if you would like.

 

[Insane Reefer]

Brown as in a nice golden brown? Sort of powdery looking?
If so, sounds like diatoms.
How long has the rock been in there?
I get a diatom bloom first off within a week or so of adding rock, but that dies off really quickly, like in two weeks or so. The a green algae that is hard, but not coralline will cover my rock, and then a maroon algae that may or may not be coralline starts - by 4 months, green and maroon dominate the rock, but pink and purple coralline start to show about then. Within a 9 months from the day you add it, you should have about 75% coralline coverage, or at least that has been my experience.

 

[Azazael13]

gold brown like I like my marshmallows

Rock was put in on Saturday I think it was.

 

[Insane Reefer]

Do I get a prize? lol

I'm surprised it isn't covering the rock though - is it "down-stream" from the flow - maybe getting pushed to where it is on the sand?

Anyway, it probably is from the rock, and the time-table I outlined for algae growth is fairly typical from my observations - so let it go for a bit and watch your hermits and snails get fat and sassy.

 

[Azazael13]

oh it is on the rock too, but it is at the end of the stream. At least I have my excuse to go get some more snails to clean up the mess

 

[Travis L. Stevens]

What is the minimum time they need to sit there in that tub? What is the purpose for them to sit there?

The longer the better, as when it sits there, it allows the cement to form the C-S-H bonds that give it strength. The longer you wait, the stronger it gets and less Ca(OH)2 is available to spike the pH of the water. The current tests that IR, me, and others are doing are putting it in a heated, moist environment to help speed up the process of strengthening and decreasing excess Ca(OH)2. If you want to participate in the experiment, then follow IR's directions. If you just want rock, play it safe and wait a couple weeks.

eaj, looks great. Keep it up.

Insane Reefer: I know you know that I've made plenty of rocks in the past, but as far as my comments on the newer methods go... Even though I waited a lot longer to bake my rocks, I noticed a substantially less amount of smell while baking them. My very first batch of rocks that I made smelled like dirt from the oven, but I barely noticed a smell at all when I baked the latest batch. I'm wondering if what we are smelling is the waste chemical/product that is being created when the C-S-H bonds are forming. Smell could be an indicator of a rock's readiness. It's just a thought.

Azazael13: I've never had a problem with rocks and algae. Like most algae related issues in the tank, I assume it is something in the water and not from the rocks (nitrates, phosphates, lighting, CO2, O2, Iron, etc). Something else to consider is that new rock added to a tank gives the perfect opportunity for algaes of all types (unicellular, nuisance, macro, etc) a chance to cling to something without competition. There's nothing to fight for nutrients, nothing to block it, etc. It's like building a new 4 bedroom home and putting a putting a "First come, first served for free" sign in the yard. It's normal to get growth on newly added "clean" rocks, but it's not the cause of the algae. I'll echo what IR is saying about the maturation process of the rocks as well. You'll go through these phases and it is normal. The severity of these phases is dependent on the tank's water parameters itself. If you have a top notch, low to no nutrient tank, then the subsequent blooms will be short lived. The more available nutrients, the longer it will take. Just a fact of life even if it was Man Made or Base Rock.

 

[Insane Reefer]

Try Abalone if you can find them - these are pretty cool and good diatom eaters.
JMTC

 

[Insane Reefer]

<a href=showthread.php?s=&postid=10005350#post10005350 target=_blank>Originally posted</a> by Travis L. Stevens
The longer the better, as when it sits there, it allows the cement to form the C-S-H bonds that give it strength.

I have to question this statement as it pertains to this experimental process, Travis . Block companies pour and bake on the same day from what I can gather. But they still must meet the ASTM strength standard before shipping out. This strength standard is based against the "Magic 28 days" for 90% hydration By their process, they make cement blocks in hours that would normally take a month. I'd say that if waiting helped, they would, but they don't. I really feel that baking as soon as it is feasible is the way to go. I am thinking about how to make sand cast rocks that I can bake as soon as I cast them. Maybe I can foil wrap the whole mess - make it look like "Jiffy Rock". :lol:

I'm wondering if what we are smelling is the waste chemical/product that is being created when the C-S-H bonds are forming. Smell could be an indicator of a rock's readiness.

So are you saying that lack of smell might mean the rock is done, or that lack of smell means nothing happened?
I'm leaning toward "nothing happened", but then, I could be wrong - guess we will have to wait and see results and try to extrapolate from the data. It does seem that the sooner it is baked, the worse the smell, whatever that might mean chemistry-wise, I do not know...
I have a friend that has a gas chromatograph? - it only needs about $500 worth of work to be functional again. We could always take up a collection, get it fixed and run some chromatograph tests - that might shed some light
I wish...:rolleye1:

Oh!!!
And for those who are tired of strips and reagents, check this out
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260121385477

 

[medic29]

Well, my rocks have been baking for about an hour. I have a tarp strung up in the entrance way between the kitchen and the livingroom. I can't detect any smell as of yet. But I also have a large floor fan sitting on the table blowing air out through the window.

I'm not sure I'm the smartest cookie in the box when I chose to bake these on the hottest day of the year so far, it is going to be around 90 this afternoon. It is alread hot and muggy outside. Because of this I had to leave the air on.

 

[Yinepu]

So what is the "ideal" PH we are shooting for? Anything below 9?

 

[Travis L. Stevens]

I have to question this statement as it pertains to this experimental process, Travis . Block companies pour and bake on the same day from what I can gather. But they still must meet the ASTM strength standard before shipping out. This strength standard is based against the "Magic 28 days" for 90% hydration By their process, they make cement blocks in hours that would normally take a month. I'd say that if waiting helped, they would, but they don't. I really feel that baking as soon as it is feasible is the way to go. I am thinking about how to make sand cast rocks that I can bake as soon as I cast them. Maybe I can foil wrap the whole mess - make it look like "Jiffy Rock".

I meant for a non-baking purpose. If your going to bake, I agree.

So are you saying that lack of smell might mean the rock is done, or that lack of smell means nothing happened?
I'm leaning toward "nothing happened", but then, I could be wrong - guess we will have to wait and see results and try to extrapolate from the data. It does seem that the sooner it is baked, the worse the smell, whatever that might mean chemistry-wise, I do not know...

Both, really. In my case where I didn't smell anything at first, I would guess not much happened at all. But cooking rock over a longer period of time, I would guess that the rock would have a decreased smell over time. Of course, if you're in the smell the whole time and/or without proper ventilation, you'll never know when the smell is truly going away. The whole olfactory burnout thing...

And for those who are tired of strips and reagents, check this out
http://cgi.ebay.com/ws/eBayISAPI.dl...em=260121385477

Nice find! Very cheap!

So what is the "ideal" PH we are shooting for? Anything below 9?

8.3 is perfect. 8.5-8.6 is acceptable, especially in an already setup tank. This will actually release calcium and carbonate back into the water for your corals to use. Anything higher than that is risky, but it will also depend on total water volume, water chemistry, inhabitants in the tank, etc. FWIW, I aim for 8.5. Anything less than 8.3 is just playing it safe and won't harm anything. Note: All pH readings should be done in acid-free water (freshwater prefered, but secondary saltwater tests won't hurt).