NYOSReef Cement - 500 ML

Used Nyos reef cement for connecting all the pieces. After and hour I could pick the entire scape up and move it in my tank. Have this in a Fluval 13.5.

Ive used Nyos and Marco cement for building aquascapes. Compared to Marco, Nyos mixes up smoother and the end result is more clean. You need to mix it 3 parts powder to 1 part water. If you add some citric acid to the water you can extend the working time. You have to mix small quantities at a time and use a spatula or backnof a spoon to incorporate the powder with the water. Wait until it gets doughy before you try to add it rock otherwise it will be to loose and fall away from the rock. When the mixrure starts heating up (exotherming) you have to work more quickly. Marco cement gives you more time but sets up grainy.

I'm sure this product functions well when applied out of water. However, for an existing reef structure with many inhabitants, I didn't want to disturb what I'd already worked so hard to establish. I tried to use it underwater. The manufacturer and directions say this is possible. Unfortunately, I had a horrible experience with trying to do this. It basically just dissolved and clouded my water. Nothing died but a few corals were pretty upset for a while. It also did nothing to attach my rocks to each other. So now I just have loose rocks with patches of white on them.EDIT: About a day after using this in my tank I had a cyanobacteria outbreak. Completely covered all the sand and would NOT go away. I've NEVER had cyano before using this product. Spent $75 on eliminating the cyano and getting phosphate down, which had also spiked. I was afraid I might lose coral. Nitrate is at about 5 now (always at 0 prior to this) and can't get it down. Although I'm not too concerned as my coral seem to be loving the higher nitrate. That being said, I did nothing different aside from using this product before any of this happened so...

TOTALLY WORTH IT and pretty much one of only a few options for reef cement out thete. i'm in the trades so i'm used to working with mortars, grout, spackle....this stuff was very hard to get the hang of and theres not a lot in this tub so you better learn fast! I will tell you #1 set yourself up ahead of time...get a bowel of water, know what pueces your joining and mix small batches. Use a squirt of lemon/lime juice to keep the stuff "open" and workable. I used it to cement lil rubble frag pieces to make my own aquascape. i let it dry a day and am curing it now...so far no major ammonia spikes but its been one actual day in my rock cycling tub so we'll see. I also didnt test ph either so time will tell. It does feel very sturdy since the mortar cured.Tips: use/make little putty knives, butter knives, tiny margin trowel....even wooden cuticle pushers will help if ur aquascaping. seal out the air and work the cement smooth after you joinbtge two pieces together2. once you connect the 2 pieces, dont let them go or reposition....hold em tight for a minute or two so u dont break the bond3. work fast, the mortar should be the consistency of joint compund or like icecream (bad example).

Comparison to the other popular EMarco mortarPros: A sand based mortar that sets strong and to a good neutral pale brown color. Regular EMarco dries to a bright gray (or pink) that looks out of place, until coralline starts to cover it 6 months to a year down the road.Cons: Very expensive vs EMarco, probably 3-4 times more by material volume. But the biggest complaint is it sets WAY to fast. It is unworkable within 5 minutes. EMarco takes a more reasonable 20 mins.Conclusion: If you have a small job and need a quick setting mortar, you might justify the cost. But having used both extensively on my 400lb aquascape, "pink" EMarco is superior in every way

This is a great product! For the buyers that gave it a low rating, don't blame the product because you can't figure out how to use it. Is does take a little practice to get it right, it must be mixed well and to the right consistency. Believe me, it works at least 10 times better than the putty stuff, that doesn't work at all unless you also use super glue to attach the frag plug to it. Might as well just use super glue gel in that case. Since this product has a high moisture content when mixed, it binds extremely well to underwater structures and frag plugs. The only downside is you must make sure it's where you want it, or you might not be able to move it. It works amazingly well. Anyone that can't figure out how to use it, please send it to me! ;-)

Other lower reviews just don’t understand how to use it. It works great, hardens in a few moments. Save your rock dust to cover the cement before it dries. Very strong and durable

Muy buen cemento pega rápido y da muy buena firmeza