Bummer they're messing with your plants - they don't have roots to keep them down.
Won't know what it looks like until you try it, right? Might look nice with more rocks that are smaller... or flatter?
This looks cool with the large slate looking piece, and then a few other larger and smaller rocks - It might not work in your tank but a flat rock would give visual interest yet the polys could still use the space. Just an idea from a quick google search. Of course the background goes all the way around the tank in this one but..
Are you worried a poly or hulk would hurt themselves on a DW piece? That would be another way to add something visually but would be less disturbed by the polys. Not sure what Hulk would think.
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