Hi. Just noticed last night that there was what looked like a really fine piece of plant root (no more than 5mm long and about as wide as a hair) in the tank. As I watched it it started to wiggle! I then saw more, not loads, less than 10? Took a picture today, sorry it's not very good. Should I be concerened? Thanks in advance.
Those are detritus worms: worms that feed on uneaten food etc., at the bottom of the tank. They're present in all tanks to some degree, but when they multiply enough for them to be obvious it's usually a sign of overfeeding or not enough gravel vac'ing.
They're harmless, but unsightly and an indicator that you may want to adjust the amount you feed or be more vigilant in syphoning out any uneaten scraps after meals