[FONE]

Recently migrated my goldfish at work to a bigger community tank, and came in two days later to find the empty tank wasn't really empty.

There are many many of these small worms on the glass. Not sure what they are. Had been feeding sinking wafers and dry flake food to the goldfish, so I don't know if this is coming from those?

Please help let me know what these are. Thanks.

 

[Tino]

I had those in my tank before I discovered I was over-feeding.
They're harmless, in fact my fish at the time gobbled them up when I topped off the water

 

[TorontoPlantMan]

They are called planaria, you can treat with fenbendazole.