I think that’s what is in my tank, detritus worms. I moved a heater from a tank that’s all live plants with no fish (just getting it cycling and ready. I think they were on the heater. Now they are all over the walls of the tank that has my bettas bubble nest and spawn. Will it hurt the fry or adult betta to leave them for now? Next, how do I get rid of them once the fry are big enough to move to another tank?