Bonding sand over mortar in aquascape

[ClayP]

Building my first big aquascape for a 120g reef aquarium (>100 lbs rock). I've finished my first section of using motor. I ended up with a lot of the Marco rocks (40 - 50%) coated with the grey mortar. I've seen others apply cyanocrylate then sprinkle with reef matching sand. I'm thinking a faster and more uniform method would be to use two-part epoxy(used in my pond) which would be easy to brush on and cover with sand. I wanted to get any input before going with this method....any downsides?

 

[Gatorpa]

Building my first big aquascape for a 120g reef aquarium (>100 lbs rock). I've finished my first section of using motor. I ended up with a lot of the Marco rocks (40 - 50%) coated with the grey mortar. I've seen others apply cyanocrylate then sprinkle with reef matching sand. I'm thinking a faster and more uniform method would be to use two-part epoxy(used in my pond) which would be easy to brush on and cover with sand. I wanted to get any input before going with this method....any downsides?

Never done this but mortar is very alkaline, prob need to cure before setting up system.

 

[Jekyl]

Can mix some sand with it. In the end it will be covered up anyway.