Making liverock/aragocrete

[worley]

For my new tank, I'm going to be doubling up the amount of liverock, as the new tank is double the side of the current tank... (3x2x2 -> 6x2x2).
To save on money, and for fun, I'm going to try and make some "aragocrete".
It's essentially cement mixed with some sort of fish safe substrate, like aragonite, crushed coral or crushed oyster shells, then shaping it to looks like liverock, and curing it for 2 days in air, and 6-8 weeks in fresh water.
I've read quite a lot about it, and the big issue with it appears to be making sure the cement is properly cured. This can be checked by testing the PH of the water before the rock goes in and a few days after, while stopping any airation of the water to see if the PH has risen. If the PH stays stable then it should be cured, if not, replace the water and check again in a few days..

I'm going to try my own recipe for my "aragocrete" / "livecrock":
cement
crushed coral gravel
perlite

The perlite should be fish safe (not 100% sure though), and it will decrease teh weight of the rocks, as it is essentially volcanic glass with tiny airbubbles trapped inside.

For further reading:
http://www.geocities.com/CapeCanaver...ementRock.html
http://www.athiel.com/lib10/rockmaking.htm
http://www.athiel.com/lib11/garfcont1.htm

If anyone has any experience with making their own liverock, please share with us!

[reef4girl]

Did you start this project yet? I am curious how the rocks turned out. I maybe getting a 75 gal tank and I will probably Diy some rock myself. Got any pics?

[worley]

Hey reef4girl, I've started on it already, I'll post some pics shortly.
A few notes, I tried using perlite to make it lighter, this however doesn't work at all, it makes the rocks brittle and crumble under little pressure, however taking the perlite out helps. Likewise, using crushed coral in too high proportions also makes the rock too brittle.
I have to say, it's very very hard to make the rocks look real in terms of shape, there is definately an art to moulding the rocks.

[CHOMPERS]

Try rock salt for your aggregate. Use one part Portland Cement Type One to four parts rock salt. You need to mix the cement first really thick (dry) because when you add the salt, it will thin up a bit. (Oh, by the way, you can't mix the salt and dry cement before adding the water.) I formed the rocks in crushed coral but on the GARF site, they made it in calcium carbonate sand. A fellow fish nerd was at my house and saw them in the crushed coral and said it looked like a giant cat box with giant cat turds. :cry:

I'll post pics soon.

[worley]

lol that desccription pretty much fits ours too, I've not had the time to even cure them in water yet!

[Moe]

I made some el cheapo DIY rocks, I used cement, salt and sea shells. Dumped them in some rock pools and now they look like this:

before



after



heres a natures own



Too bad I cant really harvest it without taking most of the life off. Its all temperate marine here in Melbourne. I think a lot of the critters would do OK as our summers get hot and the rock pools heat up to easy 30+ degrees (Celsius) on some days.

[allnatural]

i was on line looking for oyster shells for my diy lr and ran across a site that showed an experiment using oyster shells in fw and besides the basis of the experiment what was shown was that the oyster shells raised the ph levels dramatically. needless to say i did not use oyster shells in my agrecrete rocks. i did however have a lot of fun making my own rocks and by the third batch i found my designs had much improved and i actually have some really cool looking rocks soaking. at one of my lfs a guy made a rock that looks like a gnarly mask with fish shells as fangs and hair. not for me but i could tell he had fun making his own rock and that your imagination is the only limit. and the fact that he had it displayed in his 180 dt assurred me that agrecrete rock is reef tank safe if cured correctly.

[Moe]

Yeah this probably isn't a good idea for all tanks... this is best for marine tanks and possibly African cichlids tanks.

[MorganAtlanta]

Not to be discouraging to people, but I made some aragocrete DIY rock and wasn't thrilled with the results. It was too hard to get interesting shapes and I didn't like the structure of the pores that the water softener salt left. It looked "unnatural". I ended up tossing it and just going with Pukani dry rock from Bulk Reef Supplies. The pukani rock is easy to zip-tie or cement together to form interesting reef aquascapes. It was much easier than trying to build up structures with DIY rock.

The one way I would still consider using aragocrete rock is as an alternative to a bare bottom tank. If you didn't want a sand bed, you could create a custom aragocrete bottom with some interesting topographic structure, but no holes to trap detritus. You could cover the bottom with a field of GSP, palys and zoas. I think that would look really cool, and would be inexpensive and easy to do. Think of the look of moss around the base of a bonsai tree.