Rock structures were made with Polymorph.
https://reefbuilders.com/2016/10/10/polymorph-plastic-has-tremendous-applications-for-aquariums/#
This stuff is so easy to use and cheap.
Just melt in sub-boiling water.
and use to fasten rocks together.
Push some sand or rock chips in to areas that will be exposed (I was too late to do this fully)
and you have SOLID bonds.
This will be the sump, just using it so I don't scratch the display while messing with aquascaping.
https://reefbuilders.com/2016/10/10/polymorph-plastic-has-tremendous-applications-for-aquariums/#
This stuff is so easy to use and cheap.
Just melt in sub-boiling water.
and use to fasten rocks together.
Push some sand or rock chips in to areas that will be exposed (I was too late to do this fully)
and you have SOLID bonds.
This will be the sump, just using it so I don't scratch the display while messing with aquascaping.