Cement for Rocks

[liverock27]

I am trying to attach some live rock together permanently. I am looking to see if there is any reef safe cement I can pick up. I tried pegging the rock together with rods, but I have now ruined several nice pieces. Thanks.

 

[chull13]

Type II Portland Cement is what most people use for DIY live rocks. The only thing about cement is that you have to let it cure for a really long time or it will mess up the pH in your tank.

 

[liverock27]

Thanks for the quick response. This rock will be in a holding tank for probably another couple weeks before my new tank is done. Do you know where I can pick this stuff up at?

 

[liverock27]

Thanks. I guess I am off to the store.

 

[chull13]

HD or lowes. It is pretty cheap... I think like $10 for a 100 lb bag. There are a lot of threads on RC about how to make your cement rocks look natural. A lot of people mix rock salt in with the cement and as it cures the salt dissolves and gives the cement a porous look. Search " DIY Rocks" on RC

 

[liverock27]

Thanks for the tip. I am just looking to get something to help hold together the rock I have and I know reef puddy won't do it from past experience.

 

[olds350racer]

You can also get some 2-part like...
http://www.marinedepot.com/ps_ViewItem~idProduct~BA1291.html">http://www.marinedepot.com/ps_ViewItem~idProduct~BA1291.html</a>
Not this brand in particular, but I've seen something similar in a few LFS.

 

[liverock27]

I didn't know if that would be strong enough to hold the rock together.

 

[saltwater junky]

i use siliacone

 

[liverock27]

saltwater junky;163046 wrote: i use siliacone

That seems like a really good idea. It has to be reef safe since they use it to put together tanks and I wouldn't have a 100lb bag of cement laying around.

 

[liverock27]

This rock work will not be going into an aquarium for at least 3 more weeks. I have it in a rubbermade tub in the basement with a heater and some PHs for circulation. Couldn't I just use the same silicon that we use to put baffles in our home made sumps?

 

[daitheflu20]

Cap. Bay had cement for sale that should work. If I remember correctly, it was a 2-part system that cures when mixed. I believe it will cure underwater and is specifically made for aquarium use. Maybe someone there could offer more information.

 

[johnr2604]

So why wouldn't good old fashion aqua mend from home depot work?

 

[liverock27]

johnr2604;163069 wrote: So why wouldn't good old fashion aqua mend from home depot work?

I just got back from HD and looked at the aqua mend while I was there. No where on it does it say it is safe to use with aquariums. The suggested uses are for pools and bathtubs, so i am not sure if it would be reef safe or not.

 

[liverock27]

Any one ever try

 

[derek_s]

I am 'building' with my LR for my 92, and I'm curious how you ruined the LR you were putting rods in? It should have drilled easily, I would think? Are you using a hammer drill and masonry bit?

 

[liverock27]

corvettecris;163103 wrote: I am 'building' with my LR for my 92, and I'm curious how you ruined the LR you were putting rods in? It should have drilled easily, I would think? Are you using a hammer drill and masonry bit?

I used masonry bits, but I drilled all the way thought my bottom rock and today when I went to pull it out to add some new rock it cracked in half. I am trying to find something so i can put my large bottom rock back together and also to use for some over hangs I want to create.

 

[johnr2604]

LiveRock27;163084 wrote: I just got back from HD and looked at the aqua mend while I was there. No where on it does it say it is safe to use with aquariums. The suggested uses are for pools and bathtubs, so i am not sure if it would be reef safe or not.

Its reef safe. I use it in mine. Same exact stuff they sell at marinedepot just not purple.

 

[liverock27]

johnr2604;163105 wrote: Its reef safe. I use it in mine. Same exact stuff they sell at marinedepot just not purple.

Well that saves me from driving all over town to lfs or ordering it online. Thank you.

 

[derek_s]

Hmm, I was wondering, because I was planning on this method. What kind of rods and where did you get them? Also some people use black zip ties. I have thought about trying that too.

Off topic, but are you planning on raising the rock off the bottom any? I am trying to decide if it is worth propping up off the bottom or not. Somebody on here even propped their rock formation above the sand slightly, so there was water flow beneath it.