DIY Live Rock

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A place near New Orleans, La called Coral Connection makes their own Live Rock using the following. White Portland Cement, crush coral, and acrylic shavings. They sell it for $2.50 per pound. So, do the math if you needed 100lbs.

I couldn't find the white so I tried the gray. After making some rock about a month goes by and fresh water changes everyday, PH is still at or above 8.8 (PH strips on went that high). Frustrated, I wanted to try white Portland.

With that said, I went out to my local building supply store to buy my white Portland cement. It took for ever to find this but at 16 bucks for 92lbs, I'm not complaining. So, I made me three large pieces, using 2 parts crushed oyster shell, 1 part WHITE Portland cement, and 1 part salt rock. I rinsed the rocks with fresh water until the salt rock melted. Formed it and let it stand for about 24hrs.

During my water change in my tank, I put the old salt-water in a large plastic tote bin, with some of my sand from the tank, a small piece of seeded rock from my tank, a 10k 30" PC light and a power head. The rock has been in the water for about a week and I tested the PH with test strips, which according to the color chart the PH is between 7.8-8.4. (color is in between)

Coraline is seeding on this rock that I made and the white looks more appealing than the gray. I don't know why the cure time was short; maybe to do something with the white cement? Just wanted to share my experience.
I think it's the freshwater in the first batch being tested with a saltwater PH test kit and using saltwater in the second batch with a saltwater PH test kit. White must look clean, but it all gets covered with coralline and other growth soon enough. But it's good to know that white cement works great too. We had a few questions on white cement and you have answered some of them.
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That is interesting that the white doesnt spike the PH, it makes me wonder what is making that happen (if there is something added to it or something is missing that isnt in the gray).

As far as I know it doesnt matter if its salt or freshwater for pH tests. They all work the same, the difference is in the color chart. FW pH chart will just have the colors for a lower pH while salt water has its chart colored to monitor a higher pH.
Yeah, I have Quick Strips which does hardness, ph, alkaline, nitrate, nitrite, and another. They are separated color charts for fresh & salt.

Now looking how white portland is made via google, its the same process except:

White portland cement is made from raw materials containing little or no iron or manganese, the substances that give conventional cement its gray color. (from a cement website).

This may or may not have something to do with it. But the white does look good and I want to see it covered with Coraline algae. The brand of white portland is Holcim. I'm now changing my 55gal from planted to a reef or FOWLR. I'm unsure though:confused:
some rock I made

The two rocks on the left hand side are the same rock from diff angles

This is just a bit of the rock that I have done so far... this was my test rock

this was 2 batches ago for mine. getting close. i like how it slurps water when you dunk it. you know its porous then.
Finally here are some pictures of my DIY rocks





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.
hows the curing coming along? im still sitting at 8.8+ taking longer then i thought to cure. but could be cause i have alot of rock on my water suppy?
Those are some nice looking rocks.
Yes the curing can take some time, more so if the water volume is small and that makes the leaching out of the lime allot slower. But you must admit it's fun and you can save a ton of money.
scan this site for DIY rock, read through the threads and most of your Q's will be answered.
I'm sorry for being so Rudd. Thank you for your Service to this Country and Be safe. My major difference is in the filler used. I like Oyster shells and aragonite sand with motar cement. Others have use Oyster shells, sand and rock salt. Some people have used popcorn and the list goes on. The reason for this is to get the rock as porous as possible as well as being as light as possible. Standard 3,2,1 proportions in cement mixing is norally use. I hope this helps.
I did a search and I didn't really come up with anywhere NEAR the information on this thread and it is really old. I figured I wouldn't want a calcium base but figured aragonite might still work, or maybe just normal aquarium gravel. Thanks for any help and sorry for cluttering the thread with non live rock questions.
i dont see why you couldnt use the same stuff. i would definetly use white portland thou for fw cause you wont have the coralline algae to change the look of it.
I am actually thinking the darker would look better and the "live rock" holes sound awesome because I would be able to more easily anchor java moss to it...or so is my postulation. I was thinking that crushed shells would cause problems with the water chemistry. Thanks for the help!

EDIT: Since I don't want to clutter this thread and couldn't find anything with the search I started my own thread. Here is the link if anyone has any more comments without cluttering this thread. Thank you all for the help so far!
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