The 6 well plate knowledge base
The problems that actually cost runs at 6 wells, written down: whole-plate edge effects, moving protocols between formats, and colony work done cleanly.
Six wells is the smallest experiment the family sells, and its failures are correspondingly personal: one bad well is a sixth of the data. These are the failure modes that account for most spoiled 6 well work, and the working rules that prevent them.
Evaporation when every well is an edge well
Perimeter wells evaporate faster than interior wells because they border the plate's outside air gap. In a 2 by 3 grid, all six wells are perimeter wells; there is no sheltered position to compare against, and the whole plate drifts together, concentrating media and anything dissolved in it over long cultures. The drift is uniform enough to miss and large enough to matter in differentiation and dose work. Working rules: keep volumes at the top of the 2 to 3 mL range for long cultures, maintain the incubator humidity pan and check it weekly, avoid stacking plates so lids seat evenly, and feed on schedule rather than topping up irregularly, because irregular feeding makes the drift a variable instead of a constant.
Scaling between formats by growth area
Protocols move between 6, 12, 24, 48, and 96 well plates by area, not by habit. Flat bottom growth areas are about 9.5, 3.8, 1.9, 0.95, and 0.32 cm2. Seeding density, transfection reagent per well, and coating volumes scale with those numbers: a condition seeded at 10,000 cells in a 96 well wants about 300,000 in a 6, 120,000 in a 12, and 60,000 in a 24. Media volume scales less mechanically, because depth affects gas exchange, but area is the right first approximation, and the 6 well plate, where the culture is fully visible, is where a mis-scaled density is easiest to see and correct on the next run.
Cloning and picking in 6 wells
The format's signature work is colonies: seeded sparse, grown apart, stained or imaged, and picked by hand. Practice that keeps it clean: seed from a true single-cell suspension and verify at the microscope within a day, because a colony from two cells is a mixed clone with good PR. Mark picked colonies on the plate map and on the plate underside, in that order, since ink on plastic under a well is easier to trust than memory. Expand picks into their own wells promptly; a picked colony left among its neighbors is a contamination race. And record the parent well for every expansion, because months later the only question that matters is where a line came from.
Watching a culture: what the big well is for
A 6 well culture can be assessed by eye and by microscope across its whole area, which smaller formats cannot offer, and that visibility is a quality system: confluence judged honestly rather than extrapolated from a 96 well's keyhole view, contamination caught at the first colony, differentiation seen as it spreads. The labs that get the most from the format look at their plates daily and write down what they see; the map template's notes fields exist for exactly that record.
Related guides
Common questions
Why do all my 6 well cultures drift over long incubations?
Evaporation, applied evenly. Every well in a 2 by 3 plate is a perimeter well, so the whole plate concentrates together over days. Keep volumes near 3 mL, maintain incubator humidity, and feed on a fixed schedule so the drift stays a constant across conditions rather than a variable between them.
How do I convert a protocol from 12 well to 6 well?
Scale by growth area: a 12 well offers 3.8 cm2, a 6 well 9.5 cm2, two and a half times. Multiply the seeding number and transfection mix by 2.5, move media volume into the 2 to 3 mL range, and confirm density at the microscope on the first run.
How many colonies should I pick from one well?
Pick the few best isolated colonies rather than many crowded ones: isolation is the evidence of clonality. Three to six well separated colonies per condition, expanded and tracked separately, gives redundancy without merging lines. Record each pick on the plate map with its parent well.