# 3 Portland Cement
- Thread starter jc8745
- Start date
Travis L. Stevens
New member
I've made both frag plugs, rocks, and the rubble+foam. Here are my experiences.
Rubble + Foam
http://reefcentral.com/forums/showthread.php?s=&threadid=875880
DIY Rock (well worth reading the ENTIRE thread as it covers just about every aspect of making rock)
http://reefcentral.com/forums/showthread.php?s=&threadid=807988&perpage=25&pagenumber=1
Rubble + Foam
http://reefcentral.com/forums/showthread.php?s=&threadid=875880
DIY Rock (well worth reading the ENTIRE thread as it covers just about every aspect of making rock)
http://reefcentral.com/forums/showthread.php?s=&threadid=807988&perpage=25&pagenumber=1
jokeloma
Premium Member
Travis can you guess what the cost per lb was, We are getting ready to do a club buy with Bulk Reef Supply and they have this rock on clearance.
www.bulkreefsupply.com under eco rocks at 1.19 per lb
Of course I understand jc8745 may just want to do this a project or have access to the cement.
www.bulkreefsupply.com under eco rocks at 1.19 per lb
Of course I understand jc8745 may just want to do this a project or have access to the cement.
Travis L. Stevens
New member
Well, it depends on what you look at "costs". I like to just look at the material, and not the time or other kuring methods. You're looking at about $20 for 2 40 lb bags of sand and $15 for a 92 lb of portland cement. So, for abotu $35, you can make about 200lbs of rock (adding the weight of the water that bonds with the cement). as far as Kuring it goes, you could spend a lot of money with replacing kuring water unless you're using something like ro/di waste water that you would normal have run down the drain or other things like that. There are also other kuring methods that not everyone has access to that would reduce the kure time; thus reducing the cost of kuring.
jc8745
New member
jjmcat,
Does it have to be portland #3, they have portland #1 at lowes and homedepot,
which do you use,
I'm reading through travis's threads right now.
Looks like it should be a mixture of any portland and rock salt, i'd like to add in some crushed coral or rubble shells to give it some added features.
My first test batch will be a mixture something like this:
salt - portland - crushed coral
4 - 1 - 1
Does it have to be portland #3, they have portland #1 at lowes and homedepot,
which do you use,
I'm reading through travis's threads right now.
Looks like it should be a mixture of any portland and rock salt, i'd like to add in some crushed coral or rubble shells to give it some added features.
My first test batch will be a mixture something like this:
salt - portland - crushed coral
4 - 1 - 1
Travis L. Stevens
New member
jc, please read through the entire thread of the rock. it will be well worth the time put in to it. Me and Insane Reefer have put a lot of work in the science behind cement to understand how a reefer can make rock, make sure it has ample voids for top notch filtration, and to have it ready for the aquarium as quickly as possible.
Though salt is a welcome addition at making voids, there are special techniques in folding in the salt in order to to preserve the integrity of the rock. You might be want to look in to 1:1:1 with salt:cement:sand or 1:1:1:1 with salt:cement:sand;crushed coral. using only crushed coral in the mix leaves the remaining rocks with lots of jagged edges. While it doen't seem to effect anything, it can really wreak havoc on the finger tips while moving rocks or rubbing against them.
My typical technique is to put all the dry ingredients in (minus the salt), and mix it until uniform. Then add water a little at a time until the consistency is like loose clay. You don't want any extra water than you can help, but you don't need it so dry that it crumbles apart. I test my consistency by balling it in the corner of my mixing bucket and lightly tapping it with my hand until the surface is smooth. it brings the water to the top and you can see and feel how wet it really is. It should become like a jelly. If it's still crumbly it's too dry. If a layer of water forms over it, it's too wet. When the desired consistency is where you want it, then you fold in hand fulls of the salt. You have to do this as fast as possible and not over mix it. The more aggitation that is caused, the more the salt is likely to melt and weaken the matrix to the point that it can crumble to the slightest touch. If done right, the rock will last years. So, to some it up:
1) Mix dry ingredients without the salt
2) Add water to consistency adding cement if you get it too wet
3) Quickly fold in the salt as fast as possible
4) Create your masterpiece
When it comes to making the rocks, I prefer to put them on a hard surface and just kinda lightly drop clumps on to itself until I form a randomized mound. Then I push in the bottom of it so the back side isn't so flat. You can also take a bucket filled with sand or even salt and dig out indentions and fill it with the cement to make unique formations like caves, arcs, etc.
When done forming the rock, you'll need to have it sit for 24-48 hours before picking up. If available try to keep it in a very warm and humid place for the next 7-14 days. This makes sure there is ample hydrogen to bond in the cement matrix to make the integral strength even better versus just letting it air dry. Since we all aren't commercial cement block makers, we won't have access to their special curing chambers of high pressure, high heat, high moisture rooms to flash-cure these in a week or less. So, after the initial stage of the rock curing (IE strengthening), it's time to release any built up calcium from the cement in the rock. This means soaking the rocks in water. Changing the water as often as possible, making sure the water is warm so reactions can happen faster, and that the water is aggitated and moving so more fresh freshwater continues to flow over the rock are all large factors determining how quickly the rock "Kures" (releases calcium) and is ready for the aquarium
To clarify some confusing vocabulary, the cement industry uses the term "Cure" to explain the process of the water bonding to the cement. When cement is fully cured, 100% of the water is bonded to the cement. Time is the main factor in determining this. Speeding it up means keeping it in optimal conditions (IE Curing Furnace at a cement block company). The term "Kuring" was coined by a fellow reefer to eliviate confusion between the terms. Because reefers don't have access to these fancy machines that cure the rocks for us, we have to wait for the initial strength to set up enough and then we have to wash out the excess calcium carbonate in the rock, or it will spike the pH of the aquarium. Since we don't need enough strength to hold up a house, having it be strong enouh to hold a few hundred pounds is more than enough. So, letting the rock cure for a couple weeks and then letting it kure for about a month to wash out any extra calcium carbonate will leave you with a strong, chemically-inert man made rock
Though salt is a welcome addition at making voids, there are special techniques in folding in the salt in order to to preserve the integrity of the rock. You might be want to look in to 1:1:1 with salt:cement:sand or 1:1:1:1 with salt:cement:sand;crushed coral. using only crushed coral in the mix leaves the remaining rocks with lots of jagged edges. While it doen't seem to effect anything, it can really wreak havoc on the finger tips while moving rocks or rubbing against them.
My typical technique is to put all the dry ingredients in (minus the salt), and mix it until uniform. Then add water a little at a time until the consistency is like loose clay. You don't want any extra water than you can help, but you don't need it so dry that it crumbles apart. I test my consistency by balling it in the corner of my mixing bucket and lightly tapping it with my hand until the surface is smooth. it brings the water to the top and you can see and feel how wet it really is. It should become like a jelly. If it's still crumbly it's too dry. If a layer of water forms over it, it's too wet. When the desired consistency is where you want it, then you fold in hand fulls of the salt. You have to do this as fast as possible and not over mix it. The more aggitation that is caused, the more the salt is likely to melt and weaken the matrix to the point that it can crumble to the slightest touch. If done right, the rock will last years. So, to some it up:
1) Mix dry ingredients without the salt
2) Add water to consistency adding cement if you get it too wet
3) Quickly fold in the salt as fast as possible
4) Create your masterpiece
When it comes to making the rocks, I prefer to put them on a hard surface and just kinda lightly drop clumps on to itself until I form a randomized mound. Then I push in the bottom of it so the back side isn't so flat. You can also take a bucket filled with sand or even salt and dig out indentions and fill it with the cement to make unique formations like caves, arcs, etc.
When done forming the rock, you'll need to have it sit for 24-48 hours before picking up. If available try to keep it in a very warm and humid place for the next 7-14 days. This makes sure there is ample hydrogen to bond in the cement matrix to make the integral strength even better versus just letting it air dry. Since we all aren't commercial cement block makers, we won't have access to their special curing chambers of high pressure, high heat, high moisture rooms to flash-cure these in a week or less. So, after the initial stage of the rock curing (IE strengthening), it's time to release any built up calcium from the cement in the rock. This means soaking the rocks in water. Changing the water as often as possible, making sure the water is warm so reactions can happen faster, and that the water is aggitated and moving so more fresh freshwater continues to flow over the rock are all large factors determining how quickly the rock "Kures" (releases calcium) and is ready for the aquarium
To clarify some confusing vocabulary, the cement industry uses the term "Cure" to explain the process of the water bonding to the cement. When cement is fully cured, 100% of the water is bonded to the cement. Time is the main factor in determining this. Speeding it up means keeping it in optimal conditions (IE Curing Furnace at a cement block company). The term "Kuring" was coined by a fellow reefer to eliviate confusion between the terms. Because reefers don't have access to these fancy machines that cure the rocks for us, we have to wait for the initial strength to set up enough and then we have to wash out the excess calcium carbonate in the rock, or it will spike the pH of the aquarium. Since we don't need enough strength to hold up a house, having it be strong enouh to hold a few hundred pounds is more than enough. So, letting the rock cure for a couple weeks and then letting it kure for about a month to wash out any extra calcium carbonate will leave you with a strong, chemically-inert man made rock
jc8745
New member
thanks,
and i am reading through your thread,
i havent bought any mix, just planning things, i am also trying to design out what type of shapes i want to make,
it looks like it would be best to make a bunch of smaller rocks and foam them together rather than make solid large rocks.
also i plan on making a couple of shelves or tables by using peices of 3/4" pvc, basically making a layer and inserting some pvc peices, let it dry, cure, then back filling with sand, making another layer and inserting more pvc, until i get multiple layers or shelves that various corals can be placed, this will also create some nice hiding places for fish and critters.
and i am reading through your thread,
i havent bought any mix, just planning things, i am also trying to design out what type of shapes i want to make,
it looks like it would be best to make a bunch of smaller rocks and foam them together rather than make solid large rocks.
also i plan on making a couple of shelves or tables by using peices of 3/4" pvc, basically making a layer and inserting some pvc peices, let it dry, cure, then back filling with sand, making another layer and inserting more pvc, until i get multiple layers or shelves that various corals can be placed, this will also create some nice hiding places for fish and critters.
jjmcat
New member
I have never used rock salt for any of the rock that I have made.The first batch I made was the portland type 3 and crushed oyster shells that I got from the feed store.I have about 35 pounds of that in my tank now.I now use the plain portland cement and whatever sand or substrate I have on hand to make my plugs with.The only thing that I have found beneficial on the type 3 cement is less kure time.Google the word agrocrete and also look at garfs site.They both have a lot of useful info.I also wouldn't cure my plugs in the back of my toilet since all my plumbing isn't PVC.I use a 4 to 1 ratio as well on the mixture.
i just made a bunch for my 240 the recipe i found to work great is somthin like 25 cups of crushed oyster shells (50lb bag $8 at atwoods), 5 cups of concrete, and 5.5 cups water. I often substituted argo sand and crushe coral in for part of the oyster shells to give it a more diverse texture. the rock salt i have no specifics except a 5 sec pour. Also there is a big cement place off 15th and between yale and sheridan is the only place i found the white cement. other can be used but grey looks horrible to me.
eddybabyhd
.Registered Member
home depot and lowes sell white tile mortar, which is portland number 1
Jamie Riley
New member
Try GARF. They have a great website that showed you how to make your own LR. I have done it a few times and it has worked well. The neat thing is you can make your rock with caves, hollow tubes,etc... It is great for growing bacteria for your tank. Let me know if you have questions, I Can help you with
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