Creative Alternative to Agrocrete/LiveRock

elijah

elijah

Member
hello everyone! I'm currently refitting my 90 gallon reef tank . Building it back up from the ground up after being in basic training and AIT for a year then being deployed for a year to Afghanistan. So, that left me to with a lot of homework to do with all the new equipment and technology that is out there. To my dismay the already expensive hobby has become a whole lot more expensive! Paying at least 350.00 for just a hundred pounds of live rock... and that's a "good "price for these days. this left me a little concerned. So I decided to look for alternatives to live rock.
Agrocrete- cement, sand, crushed oyster shells and possibly rock salt.. a great way to make cheap fake live rock..
CONS- The curing time is two plus months and it still has the possibility to raise your aquarium's PH to unsafe highs. the PH of agrocrete is 11 while a safe range for your aquarium is 7.8-8.2 .
Foam-chemical free spray foam. who am I fooling.. this stuff looks, feels and smells fake. there are no upsides to this method and it starts breaking down quickly in saltwater. plus it floats without being weighed down..
Resin/acrylic - styrofoam, possibly wooden structure, even concrete structure then covered in resin or acrylic to seal in everything to keep the material from leeching
into the water. I've seen great results from this method.CONS - the finished product always seems to look glossy and leaves no porous material or place for beneficial bacteria to grow and thrive. The finished product seems to always be boyant and has to be weighed down sink.
This lead me to research on my own and to no avail finding a probable ,cheap, safe method to replace live rock with a product that will still have the benefits of real live rock. the best alternative I could find is agrocqete... there are hundreds of ways to make it but all of them include cement which leeches lime and keeps the Ph high... So I started trying to find a safe cheap alternative to a bonding agent to replace the cement, but with the same method as making agrocrete . So here goes... my own creation.
 
elijah

elijah

Member
first I will make a list of supplies that I used in my experiment.
Supplies -
1. bulk natural non treated sand
2. crushed natural oyster shell
3. 100 percent pure clear silicone tube preferably made particularly for aquariums. If you by silicone from the hardware store, make sure it does NOT have mold resistant additives or it will kill everything.
4. some disposable gloves, latex or rubber.
5. a new bucket for sculpting
6. a measuring cup
7. a caulk gun
8 a new bucket for rinsing that will fit your finished product.
9. a container to mix your material with the silicone.
10. a thick stir stick.
11. pure rock salt with no additives.
 
elijah

elijah

Member

First, I took my bucket for sculpting and filled it half way up with sand. I then dug out I whole in the sand in the rough shape I wanted. I then put a layer of crushed oyster shell and rock salt. I lightly patted the shell and salt into the sides of the whole to create the exact shape I wanted. if you are having trouble getting the shape to stay in the sand, you can pat a little water into the sand. when I say pat, I mean very little water patted on it from your hand.
Second, I took was to fill my mixing bucket with a ratio of 2 cups sand, 2 cups crushed oyster shell, 2 cups rock salt and a tube of silicone gel. stir the mixture together trying to keep the silicone from touching the sides of the bucket so it won't stick to it.
I continued mixing till the silicone and the mixture was completely mixed without over mixing it. if you over mix it, it will begin to fall apart. don't worry if there is still mix left behind that didn't mix in. you still want to mixture to be slightly fluid so it will flow into your mold.
 
elijah

elijah

Member

oyster shell, sand, rock salt mix.

a look at the size of the rock salt.

a look at the mold in the sand, shell, rock salt mix.

mixing the components
 
elijah

elijah

Member
After you have set your silicone, sand, rock salt, shell mix into the mold let it sit overnight to completely cure. once the rock is set completely cured you can remove it from the mold and shake off the access sand.
Next fill your rinsing bucket with hot water and set the rock into the bucket.

make sure the bucket you use is either new or is a designated aquarium bucket. if you have used the bucket for anything else where chemicals or soap has been used, it will leech those chemicals and poison your rock.

once your rock is in the bucket you will notice the rock actually sinks right away because sand and shell is mixed directly into the silicone making it heavier.
let the water run into the bucket for about a half hour to keep the temperature higher. after that time let the rock sit in the water for a couple hours to make sure the rock salt melts out of the rock.
 
elijah

elijah

Member
This is the result you end up with. a VERY realistic, textured, porous, flexible, medium weight alternative to real live rock and the time consuming and long curing process of agrocrete. if you prorate the material used to create this one rock, it comes out to about 3.50 I spent to make this one rock. you would be spending about 12.00 for real live rock this same size .
You can see here than I put a small 1 inch PVC pipe elbow in the middle of the rock to make some hiding spots for little critters. I think for a first time build it turned out pretty good!





Let me know your feed back and see What you think and any suggestions you may have on this build!!?
 
beaslbob

beaslbob

Well-Known Member
Sounds like you're doing good and having fun!
Not to put a damper on all this but IMHO balancing out the tank with macro algaes allows you to use common limestone rocks from your local quarry. At my location they want $20 per ton for the stuff. But it is also very dense and that is a consideration.
But still almost anything will work as long as the macros are conditioning the tank.
Still just my .02
 
flower

flower

Well-Known Member
I think it's pretty ingenious...
There are lots of nooks and crannies for tiny critters to live, it looks really natural, and it looks messy and fun to do too. So are you going to do a tank build thread, and show us step by step how you set this all up?
...I used a silicone resin (fish tank safe) that takes a hardener...so no need to worry about air to dry. I used it on wood pieces and yep, it had to be weighed down big time. But that stuff seals everything, and the rock salt wouldn't melt as you showed us...so what kind of silicone are you using and can you show us a picture of the brand you used?
 
snakeblitz33

snakeblitz33

Well-Known Member
Flower,
The rock salt that is exposed to water would be melted away. The rock salt within the silicone that is sealed up in it won't. There isn't any danger here that I can see.
I really like the idea, although, I have seen it before.
 
flower

flower

Well-Known Member
Quote:
Originally Posted by SnakeBlitz33 http:///t/393528/creative-alternative-to-agrocrete-liverock#post_3501679
Flower,
The rock salt that is exposed to water would be melted away. The rock salt within the silicone that is sealed up in it won't. There isn't any danger here that I can see.
I really like the idea, although, I have seen it before.
I understand what you are saying...but just the act of mixing them with the resin would seal it with a coating. The stuff that I used, once dried you could soak it for a year and it wouldn't let the salt melt. The drops that fell from the wood peices that I wiped and smeared, became like a super thin plastic coating as hard as concrete.
 
elijah

elijah

Member
Quote:
Originally Posted by beaslbob http:///t/393528/creative-alternative-to-agrocrete-liverock#post_3501492
Sounds like you're doing good and having fun!
Not to put a damper on all this but IMHO balancing out the tank with macro algaes allows you to use common limestone rocks from your local quarry. At my location they want $20 per ton for the stuff. But it is also very dense and that is a consideration.
But still almost anything will work as long as the macros are conditioning the tank.
Still just my .02
nice , sounds like you have a nice commodity . although limestone leeches alkalies into the water which raises the Ph drastically he you have blot of it in your tank .
 
elijah

elijah

Member
Quote:
Originally Posted by Flower http:///t/393528/creative-alternative-to-agrocrete-liverock#post_3501604
I think it's pretty ingenious...
There are lots of nooks and crannies for tiny critters to live, it looks really natural, and it looks messy and fun to do too. So are you going to do a tank build thread, and show us step by step how you set this all up?
...I used a silicone resin (fish tank safe) that takes a hardener...so no need to worry about air to dry. I used it on wood pieces and yep, it had to be weighed down big time. But that stuff seals everything, and the rock salt wouldn't melt as you showed us...so what kind of silicone are you using and can you show us a picture of the brand you used?
thank you very much ! it actually had more nooks than I thought !! mine I actually mixed with shell and sand which I think helped with sinking it . I'll get a pic of the silicone I used
 
flower

flower

Well-Known Member
Quote:
Originally Posted by Elijah http:///t/393528/creative-alternative-to-agrocrete-liverock#post_3501724

make sure it doesn't have any mold resistor
AHH! I'm glad I asked for a picture! That is totally different than the epoxy resin I used. What I used needed to be mixed with a hardener, and after a certain amount of time it would be rock solid plastic. This thread is going to be really helpful to lots of people, Thanks for posting a detailed "How To"
 
beaslbob

beaslbob

Well-Known Member
As I remember cement does not hydrate(harded) in salt. So using the rock salt for agrocrete might not be an option for agrecrete anyway.
but using the silicon that would not apply.
Interesting.
 
T

Tom T.

New Member
My new to me 180g is sitting in my family room and in the planning stage. Elijah, can you update us on how your alternative has worked in the tank long term ?? Please ?? Thanks
 
You must log in or register to reply here.
Top