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Bristle worms and my Mercs


Staff member
Sep 4, 2006
I have never had a problem with them with any live, healthy animals, including the mercs and my merc tanks tend to grow them quite large. There is at least one living with Wiley (as in it resides in his den and tries to share food). They are ugly and get into everything (I promise you have more than 4 if you are seeing 4) but they eat the scraps that get into the substrate and help keep the water cleaner.

I did remove one of my merc to a cup on its last day to keep the worms away and let it die in peace but they are OK, if not desireable in your tank.