EternityBC's 450g 12 feet of floating fun

[eternitybc]

Next up on my immediate list is figuring on my aquascape. Since my tank is so tall I'm going to need some very high structures but I want to keep them very long and narrow. Something like below but having it raised up about 12 inches.


Or


Anyone have any experience making something like this? I'm thinking of smashing up some dry rock, using PVC or Acrylic rods then using Marco mortar to stick it all together?