Worms in tank

[stanleo]

i haven’t seen a worm in one of my tanks in years, not since I moved out of state and had to start all over again. I seem to recall they are harmless but I want to be sure. I only saw it because I was looking for fry with a magnifying glass and there it was crawling on a sword. It was about 2mm long and moved like planaria but I couldn’t decern the characteristic diamond shape of the head. They are harmless, right?

 

[Colin_T]

Planaria are considered harmless and are found in most aquariums in low numbers. If you see them swarming all over the glass then it's an indication there is something wrong with the tank.
The most common causes of them swarming is too much meat based food rotting in the substrate.
The best way to control them is regular gravel cleaning and not putting too much food in the tank

 

[NickAu]

Get some No Planaria and use as directed on the pack, that will get rid of them. If you have Mystery Ramshorn or Nerite snails you will need to rehouse them for a few weeks as no planaria will kill them.

It also kills Malaysian trumpet snails