I've seen conflicting reports on the practicality and performance of various rockwork adhesives such as putties and superglue. What is the consensus?

[Alpha_and_Gec]

As the title states, I'm looking for a long - lasting rockwork adhesive that can stick live rock together without catastrophic structural failure for extended periods of time without maintainance in preparation for adding fossorial animals in the future. I've got gorilla superglue(the gooey jelly variant) and a stick of JB waterweld, but I'm not sure if those work for long term nor am I certain of their toxicity. Any expert opinion would be appreciated.

To be entirely honest I've had all my rocks stacked like a jenga tower without any structural support outside of themselves for years, but I've never kept anything that would touch the rocks other than my tiny hermit crabs.

 

[dangles]

Did you already watch the experiments BRS did?

If not they’re a good place to start…

 

[Alpha_and_Gec]

Can't right now... my family's wifi is down for the weekend since we're switching providers, and I'm using my precious data to figure out a game plan for reducing nitrates lol

I'll certainly look at it later though, thanks!

 

[mfinn]

When I make a structure that needs to be fastened with something that will never come apart I use zip ties.
Carefully drill holes ( this type of rock crumbles like crazy ) in the rock or put the zip ties around parts that won't slip off.
Then use a puddy stick to cover the zip tie. There are a number of different products that claim to be permanent, but nothing holds like a zip tie.
I've use acrylic rods too.
IMO superglue gel is worthless for rock.

 

[Alpha_and_Gec]

When I make a structure that needs to be fastened with something that will never come apart I use zip ties.
Carefully drill holes ( this type of rock crumbles like crazy ) in the rock or put the zip ties around parts that won't slip off.
Then use a puddy stick to cover the zip tie. There are a number of different products that claim to be permanent, but nothing holds like a zip tie.
I've use acrylic rods too.
IMO superglue gel is worthless for rock.

Unfortunately I do not have any proficience for drilling holes in rocks without them crumbling on me lol, not to mention most of them are inhabited by some sessile thing that I want to keep alive. Good to know zip ties work(as they always do).

 

[Waters]

I always use marco cement for the main support then go back and fill in gaps with a superglue/sand mixture. Never had any issues.

 

[Xniv]

forget using superglue on rocks.. frag and maybe small rocks will work but those bigger ones, don't do it. I've used the e-marco 400 for all my scapes and never had any problems with it.

 

[Alpha_and_Gec]

Did you already watch the experiments BRS did?

If not they’re a good place to start…

Seems like all of these are designed for out of water use, are there any brands that cures well underwater and is relatively cheaper? the only two answers I've seen consistently are superglue and epoxy putty, but epoxy is quite costly.

I personally already have gorilla glue and a hunk of JB waterweld epoxy, but both are pretty expensive and frankly quite small.

 

[Alpha_and_Gec]

forget using superglue on rocks.. frag and maybe small rocks will work but those bigger ones, don't do it. I've used the e-marco 400 for all my scapes and never had any problems with it.

If only they sold smaller quantities... I don't reckon I need more than 2 liters of the stuff, but they sell em in massive buckets that I don't think I can ever use up.

 

[BaliReefBox]

imo super glue gel is rubbish but at the other end of the line you have 2 part epoxy putty that is stronger than cement

 

[mike550]

I’ve used two different adhesives for different situations both with awesome success. Highly recommend Marco Aquascaping mortar (read the directions on mixing mortar) when I’m trying to put together two pieces with lots of gaps. Second I had great success with Paleo Bond Jurassic Gel. It’s like a very thick superglue with a super strong bond. To make it cure faster I made a home made accelerant from a 1/2 teaspoon of baking soda and 1/4C RO water

 

[Alpha_and_Gec]

I did find Seachem CoralCrete, which my lfs seems to sell at a similar price but with twice the mass of a tube of waterweld of the same price. Has anyone had experience with this stuff?

 

[The_Paradox]

The two part epoxy putties work fine under water but you have to view them as a mechanical fastener vs chemical. If all your joints look like a “C” or “E” even if the bond fails then the mechanical properties will hold it.

As for the hydraulic cement, mortars, whatever you want to call them, I have tried a few and all failed around the 5-7 year time frame.

Whatever method I use now, the first thing I do is glue a hard coral frag to the joint. Doing that, whatever method I used only has to last a few months.

 

[e-sully]

I've tried various putties and gels without success on heavier rock. What worked for me for the aquascape of my 250-gallon FOWLR was waterfall/pond foam. This has been mentioned on R2R before. The stuff is similar to spray insulation foam. It is very sticky (wear disposable gloves) and once you start using a can of it, you really have to finish with it within a couple of hours as the spray tube will clog (instructions say to cut off the tip of the tube and re-use, but I find it clogs the full length of the tube).

It is black and tends to blend into the aquascape. To create gravity-defying structures, I provided temporary support (books, paper towel tubes, other rock) until the foam sets. Once it hardens, it is very strong. Since it tends to bubble out when sprayed, I used a box cutter/utility knife to trim away the excess foam around a joint followed by a wire brush to remove even more so only the joint itself has foam. The whole assembly was very easy with this stuff, and I could lift up large structures by the top without the rocks coming apart. Admittedly, I did this on dry rock, but the stuff is so sticky, I suspect it would work on wet, live rock. You would need to keep the rock wet for several hours until the foam sets before immersing the rock in water (similar to the way a lot of live rock is shipped anyway - in wet newspaper).

Here is what I used: https://a.co/d/4D1bNJk (also available at HD). There are probably others that are as good or better, I just went with what my local Home Depot had it stock. For the wire brush, I used: https://a.co/d/4gtRgun

I've had it in the tank for about 1.5 years. You do get some little foam bits that end up in sump/socks, especially in the first couple of months, but they are harmless and float, so easily removed.

 

[The_Paradox]

If you’re doing it out of tank use this. Just know it’s never coming apart.

 

[Doctorgori]

I always use marco cement for the main support then go back and fill in gaps with a superglue/sand mixture. Never had any issues.

forget using superglue on rocks.. frag and maybe small rocks will work but those bigger ones, don't do it. I've used the e-marco 400 for all my scapes and never had any problems with it.

Marco Cement it from space; its the only way to be sure

 

[Alpha_and_Gec]

would love to try marco if it came in smaller batches that didn't cost $50 each... that's roughly how much I paid for salt that would last me a year.