NYOS Reef Cement - 500 ML by NYOS

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.

Works perfectly for me. I glued big stones that I took from aquarium. Works fast and reliable

This product does not work as advertised. You can not use it on wet rock. If you try to apply it to the rock or coral plugs it just degenerates in the water. I waited to long to use it now I'm past the return window. Don't waste your money if you want to use this on wet rocks or frag plugs

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 together 2. 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 bond 3. work fast, the mortar should be the consistency of joint compund or like icecream (bad example).

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! ;-)