The Ultimate DIY Rocks!

[shookbrad]

Rock Structure

Rock Structure

Here is the structure the rock will be molded around. This is going into a 42G Hex that I have drilled the bottom on. I put 5 holes in it. The plywood is strictley for the forming of the rock stage. It is just a tad bit smaller than the dimensions of the tank. The over flow is a 2" pipe and the wiring pipe is 1-1/4" pipe. The CL intake is 3/4" and the CL return is two 1/2" pipes on a SQWID(however you spell it) You can see I put zip ties all over it to help provide stability for the DIY rock. I took a thin cement only mixture and painted all the pipe to help the DIY Rock stick better to the structure.

 

[onnenmd]

Brad Those rocks you made look real nice. Good work. I'm trying to learn how to make them more like that!!

 

[Insane Reefer]

Yeah - is the plate coral skeleton (rock-close-up.gif) real, or did you create that? Be really interested in hearing how it would be accomplished if you did, and these weren't just some photos of rock you want to mimic.
Skeletal framework looks good, though I would have added a lot more holes. In my experience (see gallery for one example), thin layers of cement on PVC tend to crack (took a few months) - though it does seem to stay together and not fall off - not sure if that would be the case with the added cement covering or not...
Should work ok though. it will be a cool piece, I think.

And make a run by a feed store - you should be able to find "Limestone / Calcium for Feed Mixing", which is a sand-like chicken supplement usually made of pulverized limestone, and around $3.50/#50...
Pulverized limestone might be available to you through a hardware store too.

 

[mr.wilson]

That's authentic Micronesian rock, complete with Angry Samoan Tiki Idol. Make sure it isn't cursed.

 

[goldmaniac]

<a href=showthread.php?s=&postid=10085004#post10085004 target=_blank>Originally posted</a> by nietzsche
just finished making some batches of this stuff, pretty sweet


btw, is it possible to put this on anything so the bottom wont be flat? or at what hour can i pick it up and rount out the bottom? seems like no matter how long i wait i cant seem to do this.. i waited about 4hrs or so but it breaks apart if i pick it up

To avoid flat bottoms, line the bottom of your pan or bucket with rock salt and then pour the cement mixture on the salt. that will eliminate the smooth bottoms.

If you plan on baking the rock, you still need to wait a day for it to harden. If you're going to do the non-experimental, slower way, by just flusing with lots of water, let it sit at least a week. Cement continues to harden for weeks/months.

- G.

 

[shookbrad]

<a href=showthread.php?s=&postid=10086737#post10086737 target=_blank>Originally posted</a> by onnenmd
Brad Those rocks you made look real nice. Good work. I'm trying to learn how to make them more like that!!

I should have been more clear. Those rocks are the real thing. I am using them as part of the cement mix. I will post the pics of the pieces I made last night.

Insane Reefer - That is a real coral skeliton. I plan on implanting it in the DIY rock for coral shelves. It is solid calcium and should help keep my calcium stable in the aquarium.

I can not drill holes in the pipe since they are all part of the plumbing for the entire system. That is why I added the zip ties.

 

[BOKER420]

Ok I baked my rock and now it is soaking but I forgot to drill any holes in the rock and never poked any holes either. The salt in my rock is not dissolving. I have the rock under hot water.

What else can I do to remove the salt? And since I baked it how long will it take for it to be good to put into a tank?
Thanks

 

[shookbrad]

Ok, After calling all over the Permian Basin (West Texas) I could not find any pulverized limestone. But when I called the last person I could think of they said, "If you need white sand why don't you drive over to the Monahands sand hills and just get some". I felt like such a dork. There are sand hills of pure white sand about 30 minutes from Odessa. So I am going to drive over there this weekend and scoop a few buckets up and use that for the molding material. I will take pics of the sand hills when I get some. LOL This will same me some cash too.

 

[mr.wilson]

<a href=showthread.php?s=&postid=10088196#post10088196 target=_blank>Originally posted</a> by shookbrad
Ok, After calling all over the Permian Basin (West Texas) I could not find any pulverized limestone. But when I called the last person I could think of they said, "If you need white sand why don't you drive over to the Monahands sand hills and just get some". I felt like such a dork. There are sand hills of pure white sand about 30 minutes from Odessa. So I am going to drive over there this weekend and scoop a few buckets up and use that for the molding material. I will take pics of the sand hills when I get some. LOL This will same me some cash too.

Bring some weak acid (muriatic/hydrochloric or vinegar) to test if the sand is calcareous (calcium-based). If it fizzes, you can use it (calcareous). Otherwise it's likely silica or quartz.

You should also add a small amount to a test vial of phosphate-free water to see if it changes colour (positive for phosphate).

 

[Insane Reefer]

<a href=showthread.php?s=&postid=10087885#post10087885 target=_blank>Originally posted</a> by shookbrad
I should have been more clear. Those rocks are the real thing. ....
It is solid calcium and should help keep my calcium stable in the aquarium.

Actually, real or not, it isn't going to help your calcium levels. Having calcium based rock makes no matter - unless you keep your pH so low that nothing will live in it...

But they will certainly look nice

 

[Insane Reefer]

Sand like Brad is going to collect is fine. Silica Ok - Silicates Bad.
Again, calcium based really means nothing in-tank; algae likes growing on the smooth silica grains (just like glass to them), but it doesn't put off nutrients/silicates or anything that encourages their growth.

 

[Insane Reefer]

<a href=showthread.php?s=&postid=10088152#post10088152 target=_blank>Originally posted</a> by BOKER420
Ok I baked my rock and now it is soaking but I forgot to drill any holes in the rock and never poked any holes either. The salt in my rock is not dissolving. I have the rock under hot water.

What else can I do to remove the salt? And since I baked it how long will it take for it to be good to put into a tank?
Thanks

Ok, relax Boker - the denser the piece, the longer the salt takes to release. My lab monkeys did salt and sand only rock, which is probably about as dense as what you've made, and they reported anywhere from 36-62 hours to release the rock. Even my rock, which is pretty light takes 24-36 hours.
Do you have an old powerhead, or an air pump - something to get some water movement? If not, plunge it up and down to force water through it several times an hour, when you are around to do so - this will help...

Just be patient - the salt will release eventually. IMO getting the salt out is one of the bigger hurdles...

But does it seem nice and hard? How did the bake go, do you think?

 

[BOKER420]

Well the back I started last night so I only baked it 2 hours and then this morning another hour and then 1.5 hours of cool time then in the hot water. I pulled my new pieces from their bucket this morning and I have 2 of them in the oven which will be the normal 4-6 hour bake. My 2nd batch I put in 1.5 parts salt. So it will be interesting to see how much lighter the 2nd batch is.
Thanks for the help. I'll put a powerhead in to help move the water around.

Insane Reefer I sent you an e-mail for that form. My e-mail address is billabong_4201@hotmail.com incase you didn't catch that it was me.

 

[unbreakable]

<a href=showthread.php?s=&postid=10087866#post10087866 target=_blank>Originally posted</a> by goldmaniac
To avoid flat bottoms, line the bottom of your pan or bucket with rock salt and then pour the cement mixture on the salt. that will eliminate the smooth bottoms.

If you plan on baking the rock, you still need to wait a day for it to harden. If you're going to do the non-experimental, slower way, by just flusing with lots of water, let it sit at least a week. Cement continues to harden for weeks/months.

- G.

so before I put them in water, I have to let it sit out a week before i can do it? also, when you test the pH of water, are you doing it in the freshwater or saltwater?

 

[goldmaniac]

you CAN put the rocks into water whenever they're hard enough and strong enough for you. putting them in water interrupts the Curing process which is the cement getting stronger as the bonds form. In this tread, we're calling Curing and Kuring two different things. Curing is what I just described; and Kuring is putting the rocks into water and flushing them to get the pH down to a decent (8.5) level. once you start Kuring with water flushes, the Curing (strengthening) pretty much halts.

In my tests, I could still imprint a fingernail mark into the rocks after 48 hours. After 5 days, they were hard. after 7 days, the rocks could handle me (180 lbs) standing on them and they would hold my weight without breaking.

I'm not telling you to wait. I'm only suggesting. There's no HAVE TO's on this thread, everyone is contributing their experiences and what works for them. with the salt in the cement that will eventually dissolve away, there will be some pretty thin and airy parts in the cement and IN MY OPINION it's worth it to wait to make sure that the rock/cement doesn't get brittle after all of the salt dissolves and creates all those voids that we want to have. I'd hate to go thru all this trouble and then have half the rocks break apart on me. We want that cement to be nice and strong.

When testing the pH, it's in either freshwater or saltwater. Freshwater is suggested as a) it's more available usually and b) the lower pH of 7.0 in normal fresh water will do a better job in reducing the high pH that the rocks will produce. I've heard that the pH starts out at 10 - 11, (never checked pH when starting to Kure, only weekly starting after 7 days)

BUT no rules are written in stone, here. If you have easy access to a salt water waterway, like a dock near your home, dropping the rock in that water will Kure it nicely, as well. Same goes for any running freshwater source. Everyone's pretty creative with this DIY project, that might be why it's going on 100+ pages so far.

I'm no expert, here, mind you. I've just learned more than I expected about cement


- G.

 

[goldmaniac]

And as always, PLEASE anyone correct me if i'm wrong about any of these points I'm stating about the process, here..

 

[onnenmd]

just a follow-up to nietzsche's question........are people using saltwater or freshwater ph test kits? Does it really matter a lot if you use a saltwater tester in the freshwater to determine if the rocks are "safe"?

 

[goldmaniac]

I *think* that kits designated as fresh or salt water are only using that term because of the range that the kits can cover, i.e Salt goes to somewhere near 9.0, but I don't remember fresh water *aquarium* kits going that high. Conversely, I don't recall ever seeing a 'salt water' kit providing a color comparison chart that goes down to 6.5, like freshwater kits do, i think.

I wrote way back on this thread that i got a little kit of 50 pH test strips that went from pH 5.0 to 11.0 or something on eBay, with shipping for $5 or $6. nice, wide range to test with. Accurate to only .5 of a point, but that's fine. It didn't designate freshwater or not. So I don't *think* it makes a difference.

sorry, I'm a little rusty with freshwater. no pun intended.

Hope this helps. I'm not sure it did.

- G.

 

[Insane Reefer]

<a href=showthread.php?s=&postid=10089689#post10089689 target=_blank>Originally posted</a> by goldmaniac
... putting them in water interrupts the Curing process which is the cement getting stronger as the bonds form.

Just one slight adjustment - the cure is not really interrupted - it still continues and will continue, it is just slowed as less free O2 is available...

 

[Tahlequah]

I found a place where you can buy a bunch of Litmus papers for a couple of bucks, Hobby Lobby. The range for them are (this is from memory) around 3 to 17ish. It may be more than that, it may be less than that, but it has much more range than the usual aquarium ph strips and much much cheaper.