Real lab failures, root causes, and fixes — curated and bilingually annotated by our team.
Imaging shows linear scratches, dust specks, or crystal violet precipitate that look like colonies or obscure them.
A ring of stain appears around the dish edge; cells aggregate at the periphery due to evaporation / meniscus effects.
Entire dish is deeply purple; individual colony boundaries are blurred by background staining.
Stained dish shows only very faint purple; colonies are hard to distinguish from background.
Some colonies are very large while others are tiny — suggests cells were not properly singularized at seeding.
Only a handful of visible colonies per dish; counts are too low to give meaningful statistics.
After 7 – 14 days of culture, the entire dish shows no visible colonies after staining.
Three replicates of the same group give very different colony counts. Showing only a representative image without statistics is misleading.
Staining shows blotches, smears, or uneven intensity across the dish — technical artifacts can be mistaken for real biological differences.
Many colonies fuse together so individual colonies cannot be counted reliably; counts will be over- or under-estimated.
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