The tape I used is carpet fitters tape so if I try to pull it off it will shred the backing film(which basically means binning everything and starting again) it is strong stuff, I believe it will grip the film well enough that the snake will never get behind the film, plus I have sealed the edges , plus when I put top, bottom and back on that will secure it even further.......but I'm heeding your advice and I'll check the viv every day and if I see the slightest sign that the backing film shows any sign of damage I'll make sure it's delt with immediately.