I’ve recently been having issues with my heat-killed OP50 plates. After 3-4 days of incubation, my plates that were spotted with heat-killed OP50 (75 deg. for 90 minutes) grew separate bacterial colonies that look similar to the OP50, they are smaller grouped together and have an opaque yellowish appearance. These growths do appear on the live plates as well and I initially thought they were due to splatter when spotting the plates, but the heat-killed bacteria should not produce small colonies since there isn’t a lawn of bacteria to begin with. These spots also appear on control plates that do not contain worms. I left a streak plate of the heat-killed bacteria to incubate for 36 hours and no colonies formed on the plate. This also appears on NGM plates as well as LB agar. Has anyone else had this issue?