DIY Live Rock

AJReefer

New member
Yesterday I made my first batch of DIY live rock. The recipe is as follows: 3 parts crushed oyster shell, 2 parts rock salt(crystals or whatever you want to call it) and 1 part Type I/II Portland(grey Quickrete). After 24 afters of waiting I checked on the rock and they were still not completely hardened. Just going to have to wait another 24 hours. Anyways a question my dad asked me was are you sure this is completely safe for the health of fish?
He said that cement has many chemicals which can be extremely harmful.
I'm pretty convinced of what he says is true but, if anyone can please backup or disprove please let me know.
 
You need to "Wash" it to bring the PH down and leach out the chemicals... if you have a stream or an ocean you can place your rocks in that would be best if not then in a bucket with a power-head changing the water every 2-3 days for 4-8 weeks... water doesn't need to be filtered or anything.
 
I know that they make aquariums out of concrete I know that lots of people have made and used it with out problems... I know that I'm making some
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and I know that if there is a little leaching that continues your PWC will take them out. As I said I would give it like 2 months of water flow(especially if you are concerned)
 
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Countless people have used DIY Rock. Aggregate rock I believe some call one variation. You made Oystercrete like I did. Which I feel is better since it simulates real Live rock in that it has calcium in it. You must go through at least a two week cycle in order to "cure" it I prefer doing it for two months and change the water weekly. I usually don't put them in my quarantine tank until the water shows a nuetral PH.

I used a bit more white portland cement in my DIY rocks. I mixed the salt in right before i poured so it didn't melt at all also.

And like others have already stated:

people make concrete fish tanks / rocks / structures / etc all the time. You just gotta cycle the tank or stuff you make to leech out all the chemicals which are being released while it is curing.
 
The first batch i made took almost 6 months to cure. But they were big and it was cold. I have cured some in the toilet tank, that worked good for smaller pieces and only took about 6 weeks.
 
How much rock and the size and shape will influence how long it takes to make it aquarium safe.

How much did you make?

Have you checked out the huge thread on the subject here in the DIY forum?

There is a ton of info on the subject but you have to sort through a bit because of all the discussion.
 
I've constructed a shelf peice which is about a foot long and some legs for it to stand on. I gave them about 48 hours to harden then washed it off and left them in a bucket filled with water. I'm not sure if I should have left them in the sun first but when I took them out of their moulds the sun was already gone. I'm gonna replace the water daily until it is clear then allow it sit for at least a month and test the ph. I havent even bothered testing for ph because its obviously way off the normal tap water ph level.
 
ya I plan on changing water in a kiddie pool every 4 days... I also have a submersible pump in there to push the water around... I say 4-8 weeks of that... I'm a little paranoid about the chemicals so I'll be washing it for 2 months...(all summer... don't worry I got a second kiddie pool for my kids :D)
 
Just a heads up in case you don't know but after the freshwater bath pH has stablized and you put the rock into saltwater you can get another pH spike.

If you belong to a club or have a fish store ask for some WC water from someone, replace the water, wait a few days and test the pH again. This spike is much shorter.

Somewhere within the huge DIY rock thread not E's but the original one, Insane Reefer did research on how to cut down on water use. I believe that she has a summary post of all her work.
 
Finally here are some pictures of my DIY rocks

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I like lots of hiding places... this isn't necessarily how I'm going to set it up in my tank. The size of the rock pile is approximately 2'6" wide, 2' deep, and 2' high.
 
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