THE forum and online store dedicated to Halocaridina rubra aka the Hawaiian Opae ula shrimp! 

Share photos and videos of your Opae ula setups, plus keep logs or journals for others to read.
 #3364  by AdeDunn
 31 May 2017 13:26
opae ula related wrote:
AdeDunn wrote:I see what you mean. It looks more like coated construction foam than rock.

Construction foam would be light and not heavy.

Vorteil, is it light?

Yeah, I've used foam quite a few times, and Gorilla glue, it just looks like foam. Looks kinda like a cement mousse sort of thing? Certainly doesn't look like natural rock, especially that coating on it that looks a bit like Elastopur/Epoxy or something.
 #3370  by odin
 02 Jun 2017 20:38
Maybe its made of some sort of plaster?
 #3372  by AdeDunn
 03 Jun 2017 22:52
My otherwise useless sub to PFK magazine has actually been a little useful, there was an article in there about marine aquarium decor. In it there is a description of "imitation live rock", which is apparently made of "live rock like materials" and then coated in a reef safe coating in either pink or purple. Apparently some even comes pre-seeded with bacteria. Supposedly it's the rock of choice these days, as it's easier to work with than real live rock, as it comes in specific shapes.

Still, if it was sold as live rock, and not imitation live rock, that's a heck of a dodgy move by the seller.
 #3376  by odin
 04 Jun 2017 09:31
I've read this man made stuff is good because it doesn't come with unwanted parasites but i suppose it comes with other downsides.
 #3377  by AdeDunn
 04 Jun 2017 10:58
Aye, reading the article every option has cons to go with the pros. Ocean rock is really heavy and hard to work with, and if it collapses can damage your tank. Lava rock can contain metal traces. Tufa rock disolves. Real live rock is hard to "scape" with, and can come with hitch-hikers like aiptasia and bristleworms. Resin rocks are very light and tend to be open on the back (the Unipac ones look really nice, but have no back so you can't stack them etc). Heck I knew a guy in the viv hobby who used to make his own rocks with styrofoam, epoxy and rock dust from his local quarry, but those things would float in water. lol I've even seen reefers who use Alfagrog and glue it together to build rock structures, but that is a LOT of work. :what:
 #3385  by Vorteil
 04 Jun 2017 18:43
Wow very interesting back here. I appreciate it. If there weren't an chips in it I would never have known that it's man made. It was sold out of a tank as live rock. Nothing grows on it except for the exposed areas that are chipped away of the purple coating. I've seen algae there. Didn't know lava rock could contain metal traces. How do you know if it does?
 #3386  by odin
 04 Jun 2017 18:45
I wouldn't worry about metals in lava rock, i have lbs and lbs of it and have no issues that and its fine in the wild.
 #3387  by AdeDunn
 04 Jun 2017 23:03
I use lava rock too. The article was in relation to reef tanks, where they worry far more about dissolved metals than we would need too. :wink: I'm surprised algae won't grow on the coated areas though, it usually has no problem growing on even the most artificial materials (eg. plastic.... lol).