I'm trying to get a cement to make my reef rock stay together in my new tank that i would be hopeful doing this weekend dose any one know of something i can use thanks
You do not want to use a true 'cement' as it contains lime and it would have to cure for months (in a vat of water with constant water changes) before it could be used in a reef tank.
Ha, this one I know! Hubby uses that hydraulic cement too. I am sure about that because we were shopping together when he picked that up and I remember my absolutely intriguing question: what the hell do we need cement for. So yes, hydraulic cement should work! God, so proud of myself now...