detritus worm climbing out of tank!?

[zong021]

Hi people,

Detritus worms are appearing above the water line, my guess is they climbed all the way up from the gravel.
My water parameters:
Ph:6.5 (Has tannin)
Kh:6
Gh:5
NH3:0
NO2:0
NO3: less than 10ppm
Fertiliser : 2HR aquarist
Plants : Red root floaters, amazon frogbit, water sprite, water wisteria, marimos, java moss.
Stockings: 15 White cloud minnows, neocaridinas, 1 amano, 1 otocinclus and 1 bristlenose pleco

Fishes and shrimps appear healthy and eating well. No problems with molting. Strands of algae on aquarium glass surface (they are from cycling and i am too lazy to remove them. They are not propagating). Photo-period is 8h per day. I do 10% water change weekly.

I remove the worms whenever i see them. Should i be worried? Anyone can shed some light on such odd behavior?

[aza]

How large is your tank?