Aragocrete TOTW 1-17-05

[Key Of David]

I was thinking of making some of my own rock to seed and was wondering why everyone uses so many different ingredients in their rock. Why can't you just use crushed coral and/or sand? Will coraline not grow on this?

[scubadude]

I was thinking of making some of my own rock to seed and was wondering why everyone uses so many different ingredients in their rock. Why can't you just use crushed coral and/or sand? Will coraline not grow on this?

Hey Key of David,

Im guessing that you are including portland cement as one of your ingredients too right? Theres really not much else needed to use except some of the following ingredients

Plastic carvings - this is to have been said that it gives a more rougher natural look and possibly coralline cling/grow to better. I really dont buy this thought

Oyster shell - this really would only be needed in place of crushed coral, for one its much cheaper than CC and could be considered more ecologically correct.

Dye - this is used to make your rocks more red/purplish that way it looks like its already got coralline growing on it I have used this before and I kinda like it.

Pasta shells, cheetos, rock salt - these items as well as some others floating around there have been used/tried for creating voids, and more porous rock but I have found that they really arent needed and take a long time for them to cure out of the rock.

If you have heard of other ingredients besides the ones I have mentioned I would love to hear the thoughts

[Key Of David]

Thanks scubadude! That's pretty much what I was looking for in an answer. I have a bag of crushed coral but didn't know that it would be enough to make all the rock I want to make. Oyster shells being cheap I may just add them to the mix as well. Sand is also pretty cheap so I'll be using that as well.

Thanks for that food die idea!! I would have never thought of that but one of my thoughts of making my own rock was the looks/color before it got "seeded"....which from what I gather so far could take a while. I want to put coral on the rocks but this might be far down the road.

If I come up with any "interesting" ideas as far as adding to/making the rock I'll let you know. Thanks again!

[scubadude]

The Recipe

• 2 parts sand (preferably aragonite aka southdown, but silica sand will work)
• 3 parts crushed coral or crushed oyster shell from a Feed Store
• 1 part portland cement (I use portland #1)

Other items needed

• Mixing and/or Mold tubs (below is a picture of them, I like to have 3 of them on hand one for mixing the mortar, and 2 for molds however you can use other items if on hand)
• Pair of heavy duty latex gloves (will protect your hands)
• Extra sand, and crushedcoral/crushedoystershell on hand
• powder cement dye (some like to use a red/maroon to make it look more natural from the beginning) Optional
• plastic spiral PVC shavings (drill PVC and you have the shavings) Optional
• Cheetos (yes the chips) Optional
• Pasta shells, ziti, rigatoni whatever style you want Optional
• and even rock salt Optional

First thing you want to do before you mix up your recipe is figure out which size, types, and forms of rock you want to make. The most important thing to consider when engineering your rock is POROSITY! the more porosity you have in your rock the much better for SOOO many reasons

1. It cures faster more water contact
2. less dense easier to handle
3. more holes, nooks, crannys means much more life that will live longer and be able to hide thus sustaining planktonic life forms in your tank.
4. You will see more zonal creatures and cryptic sponges, tunicates, seasquirts with more porous rocks

Ok, so how to make it porous. My young jedis I can only show you the door please open your minds and expand beyond what I give you I will show you my ideas but try and expand and share them if you have better ideas by all means please post them. Take one of your tubs and form about a 3" SB (Sandbed) on the bottom, now take your hands and form your mold into what type of rock you want to make.

You want to mix up your recipe DRY, I like to use 1 cup increments if you want to make alot of rocks still use one cup increments other wise its hard to mix a 4" layer into another 4" layer if you get my drift. For example:

1 cup of portland cement
3 cups of crushed coral/oyster
2 cups of sand

If you wanted to make twice this then do it again, then mix up all your dry ingredients so all of them are well mixed then you can add your water slowly into your mix until you get a thick runny syrup consistency (easy to pour, yet not runny)

ONLY pour half of your mold (maybe even less) at first, then sprinkle trails of sand throughout your rock, it is very important that the trails of sand are ontop of the first mold pour go from one side of the mold to the other, these sand trails will be rinsed out after the mold is dried thus creating POROSITY, now the other methods for porosity are some of the Optional items listed above such as cheetos, or pasta shells (these can be time consuming though) after rocks cure with pasta or cheetos inside them you can put them outside in an ant hill and ants will find the pasta/cheetos and will eat them thus creating your porosity The pasta has been known to dissolve but it is very time consuming and I dont sugest it unless you come up with an easy way of removal....Think creatively. Remember the ants have got to be able to get to the cheetos!

once you have created your porosity layers you can pour your next layer of cement another trick is to make your cement a slight bit thicker and drop small pieces of the thicker consistency cement mix from about 10-12" above the mold in a shaking pattern this will give a more inconsistent and sometimes more porous grain texture. After you have made your final layer you can take a small hand full of crushed coral (for this step its better than oyster shell but oyster shell will work too) and lightly sprinkly ontop of your mold (another texture tip) This is also the point where some people use the plastic spiral shavings, it is said that it helps in texture and supposedly attracts coralline algae much quicker thus boosting your life cycle onto the rocks, I have tried the plastic shavings but am not to fond of them.

[scubadude]

Now you want to let your rock dry for about 24+ Hrs, and then mist it if you want this helps in making your rock stronger....the longer your rock dry-cures the more stronger the cement is. after about 48 hrs carefully take your rock out of your mold and turn it over and rinse off the sand from the bottom (Carefully) then let it dry for another 24 hrs (these time frames may be quicker if you use outdoor and the sun is cooking and no rain) After a minimum of 36 hrs of complete drying (no misting) you can put your rocks in tubs of FRESH water for the next curing stage that I call the phosphate-cure stage this stage will detract all the phosphates (which are bad for your reef tank) out of the rock, the majority of the phosphates are derived from the portland. My most favorite way to do my phosphate cure stage is a rubbermade on the side of the house filled w/ water and a couple of powerheads and every other day I turn on the hose and let the water overflow for about a minute. You may notice after a couple of days that you will get a film layer ontop of the water, this is basically what you are leeching out. I dont recommend using this is a sign that when you dont see the film layer its cured and ready for your tank, however it is usually a good sign that you are almost ready to add your rocks to your reef tank once you see the fill start dissipating. Once your phosphates are 0 and your PH is the same as your tapwater then you are safe to put the rocks into your tank....however I HIGHLY recommend doing a little at a time and allowing atleast 1-2 weeks inbetween times of adding more rock. to seed your rock you must have plenty of natural live rock already established in your tank. Phosphate cure times can take anywhere from 2weeks - 3months, and are relative to many variables that you control....such as the density of your rock, the amount of water/rock ratio, the amount of flow, the number of times you change your freshwater during the phosphate cure, etc etc.

For faster coralline growth once you put into your tank your newly cured rocks and if you want coralline to grow, what I do is ask a freind or go to a LFS and get razor scrapings of coralline algae (usually only a buck for a ton of it) from the sides of their glass then I take a cup of my tank water and put in the blender (guys dont use the wifes blender, she will get ticked off....trust me) along w/ the scrapings of coralline algae and mix it real good....then turn off your powerheads in your tank and try to pour the coralline slurry right ontop of your newly made rocks...wait about 15 minutes and turn your powerheads on...I have even heard of some ppl taking big scrapings of coralline algae and glueing them onto their new rocks. Also make sure your Ca, Ph, and Alk levels are all up to snuff so your coralline can spread. Regardless to popular belief heavy light is NOT a needed item for spreading coralline....good flow and low lighting seems to be good conditions for coralline algae growth.

more tips
Making your own frag plugs and making rocks that will fit your own plugs are quite easy too. some use eggshells, I like to use small solo cups (these are the small plastic cups for mayonaise or condiments from fast food joints)



and here is a frag tray I made out of acrylic to hold the plugs

[scubadude]

And here you can see the areas where I made my sand trails for porosity




Others have taken and puting the rock formations around their overflows or return pipes to form a more natural look....some make ships or anchor molds. My newest approach for porosity is trying a balloon (im sure there are different dimensions of ballons too) and pouring the mold around the balloon w/ some lace texture then when it dries pop the balloon...maybe even spray the balloon w/ spam or oil so the balloon doesnt stick to the cement? You can also create rocks in stages for example here is what I call rock tripods

first you make three legs (about 6" tall) then make a large circle rock whith a hole in the center...before the circle rock dries put the three legs in it

heres pics of my tripods as well as other creations




Here you can see some of the rocks in my tank



Now one of the tripods after it has become full of life

[Key Of David]

Wow thanks for the detailed pics and instructions! I had no idea you were going to make this thread that good.

I'll definately be trying that sand trail method for making pores. Looks like a 'pods dream.

Do you glue your corals to the rock or do you place them somewhere and let them move if they want?

[Samper]

Corals don't roam around the system on their own, there might be some that do but I haven't seen or heard of anything that moves around other than an anemone and that isn't a coral. SPS frags are usually glued or attached by another method to the LR. LPS and softies are usually placed somewhere since most of them come on a rock already.

[scubadude]

Do you glue your corals to the rock or do you place them somewhere and let them move if they want?

Actually what you can do is pour your frag plugs like shown in pics above first then after they dry use one of them to indent in the rocks you make (obviously before the crete sets) so your frag plugs can fall right into place

[Key Of David]

Cool looks like I'll have to keep that in mind while I'm making the rocks then. Thanks!

[acer]

Cool looks like I'll have to keep that in mind while I'm making the rocks then. Thanks!

Hi- new to this- but thought I should point out that much of the oyster shell available is "very" toxic with meavy metals/pesticides,etc. . Do you really want to add slow poison to your tank?? Just a thought

[scubadude]

Hi- new to this- but thought I should point out that much of the oyster shell available is "very" toxic with meavy metals/pesticides,etc. . Do you really want to add slow poison to your tank?? Just a thought

Hi acer

Welcome to Reefland!

100% Crushed Oyster shell is NOT toxic and does NOT contain heavy metals/pesticides. It is obtained from feed stores and is used as chicken feed for the purpose of chickens to digest food, as they do not have teeth. Now where did you read that tidbit of misinformation I would really like to know.

[scubadude]

I figured I would add this link for reassurance
(look at bottom of the link)

http://www.shroomery.org/index/par/23439

This shows the composition of Crushed oyster shell to be mainly CaCo3. It also shows pictures of birds parrots etc. It sounds quite silly to use heavy metals and even more silly to use pesticides on something that is made for oral use by livestock.

[Samper]

In my younger days I was an active member of that site. Some good information there.

[acer]

In my younger days I was an active member of that site. Some good information there.

Hi again, My "tidbit" of information involves my profession. I am a Chiropractor and prescribe alot of suppliments,herbs,etc. I have taken many seminars regarding the subject of toxins/suppliments,etc. Every INDEPENDENT test I have seen on calcium suppliments obtained from oyster shell have trace amounts of "poisons/toxins". All higher grade suppliment companies, who sell only through doctors (not over-the-counter brands) will not use oyster shell to obtain the calcium because it s too expective to get the toxins out. ONe reason that GNC or Sams club brands are 50% cheaper. Why do you think there are rigid guidelines on eating oysters/shellfish if a woman is pregnant - they contain lead/mercury/etc.

Oysters live, well you guys are experts on that. Unless the oysters are farm raised with controlled h20 and not on the polluted coast they are going to have toxins in there shells. Manufacturers of "feeds" do not recommend that animals need filtered water either- but wee all know that a great way to kill of our tanks is to put tap water in our tanks. I doubt they are concerned with trace elements that are not obviously/easily detected. Sorry to be a pain.

[scubadude]

......Sorry to be a pain.

Acer,
You are not a pain bro....I want this kind of input thrown in here. If we dont share this then how will we ever know. You have made me more cautious with crushed oyster shells, and because of you I am researching it more now. So correct me if im wrong but your analysis or others in your field of work that have analyzed crushed oyster shells have done it for the purpose of human use? If this is the case then your statement is more so the concerns of poisons/toxins that are exposed to humans? There are many toxins/poisons in the ocean/reef that are poisonous to us but may be beneficial to the reef...correct? There are also reactions here that are above and beyond the concept of us. However with this being said I have used Crushed oyster shell for my homemade DIY rocks in my 220g and that tank had sustained very good health with the rocks residing in the tank for 10+ months. I will also state that over 65% of the rocks in my tank where DIY rocks made w/ oyster shells. I had an extensive variety of fish, SPS, softies, and inverts in this system and besides the normal cycle of the tank for the first couple of months of algae blooms I showed no toxins/poisons that I personally could relate to these rocks.

[acer]

Acer,
You are not a pain bro....I want this kind of input thrown in here. If we dont share this then how will we ever know. You have made me more cautious with crushed oyster shells, and because of you I am researching it more now. So correct me if im wrong but your analysis or others in your field of work that have analyzed crushed oyster shells have done it for the purpose of human use? If this is the case then your statement is more so the concerns of poisons/toxins that are exposed to humans? There are many toxins/poisons in the ocean/reef that are poisonous to us but may be beneficial to the reef...correct? There are also reactions here that are above and beyond the concept of us. However with this being said I have used Crushed oyster shell for my homemade DIY rocks in my 220g and that tank had sustained very good health with the rocks residing in the tank for 10+ months. I will also state that over 65% of the rocks in my tank where DIY rocks made w/ oyster shells. I had an extensive variety of fish, SPS, softies, and inverts in this system and besides the normal cycle of the tank for the first couple of months of algae blooms I showed no toxins/poisons that I personally could relate to these rocks.

Yes, my info is about human toxins, Never thought about the idea that what hurts us may not hurt them. I jsut figured it was "food for thought" . I definetly like the idea of making my own rock. If it works ---. It also maybe that the process "seals " the toxins in the rock so they leach so slowly that it does not matter. Good discussion--- thanks. I will try the process in the spring-with my kids, Sounds fun for all!!

[scubadude]

Thought I would throw these pics in too

[Key Of David]

I'm wondering why oyster shells would have something crushed coral doesn't. Isn't crushed coral from the sea too....as well as the fish we put in our tanks?

[scubadude]

I'm wondering why oyster shells would have something crushed coral doesn't. Isn't crushed coral from the sea too....as well as the fish we put in our tanks?

Well the more I think about it the more it makes me wonder....we all know that oysters can make pearls so there is a different chemistry going on w/ oyster shells....I think...Ill research it a tad more

also maybe that the process "seals " the toxins in the rock so they leach so slowly that it does not matter.

I think acer makes a good statement here too