identify the worm. If they're anchor worms prazi may not kill them. You'll need diflubenzurone aka dimilin. Or the new version dimilin X. Parasite guard by tetra also contains it, along with 3 other ingredients (prazi, Metro, acriflavone) that are a bit overkill together imo and costs a lot because you have to buy in tab packets. Dimilin cheap online. Anchor worms spilt and have two "tails" on them
If it's planaria, nearly nothing will kill them. You'll have to reduce feeding, increase cleaning and keep water super fresh and wait. They're numbers will die down as the food sources dwindle. They're not parasitic. They can cruise on fish but won't imbed like anchor worm. Seen mostly on the glass and swimming in water.
Hard to see anything in picture. Easier to see when in water.
Any way to tell what kind of worms they are? They look imbedded. I'm not big into using medicine but I will go the dimilin route if needed, I need to kill them quick before it gets worse.
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