Its the TLF. I think the weight of the rocks is just too much. I am trying to put branch rock coming off base at 45 degree angles. Not sure it would really hold up anyways. First round of aquascaping never 'sticks' (pardon the pun). Its all good think I am on v3 already.What epoxy are you using?
Try to Wedge some jb water weld it between those seams.