sound like you have insect lava infestation which may possibly be from you plants or a native insect. if one of the worm like cretins are knocked in to the water do they sink and move like a slug. or do they dance about like a blood worm?
my last check of my water was all good. but think i will go get a kit in the morning and check again. all my other fish have no problem and all seem healthy.
HI My blue lobster has what seems to be like oringey woolly looking stuff on his joints on his front arms/legs is this normal or dose he have something wrong with him?.