Have kept 3 ghost shrimp with my Betta for over a year all live peaceably in a 10 gal planted tank. A few weeks ago I bought 3 more " ghost shrimp " quarantined them in a 1.5 gal & observed that one of them looked a bit different than all the others,figured that it was nothing to bother with. What a stupid move on my part, 3 days ago I put the new shrimp in the tank and the different looking shrimp acted very bold and was following the betta and grabbed on to his tail fin poor betta was darting about trying to dislodge that mutant shrimp. The mutant shrimp was not a true ghost shrimp, don't know how it got mixed up with the ghost shrimp. The mutant shrimp no longer resides at my home.