welcome carpio1991. One way you can do some aquascaping is with some acrylic dowels/rods. You drill an appropriate sized hole with a long masonry bit and pin the two pieces together. The advantage is you could get them apart if you had to. Some people also use some plastic zip ties. If you use zip ties, once you get some coral and stuff growing, you'd never see them. Again, if you absolutely had to, you could probably take it down, which you can't do with glue.