# Check remaining cultures
A 1:1 000 dilution worked well for the -8 culture. The remaining cultures from -7 to -4 were seeded with more cells and therefore a dilution factor of 1:10 000 will be used for these overnight cultures. This is achieved through two sequential 1:100 dilutions.
{% stepper %}
{% step %}
### Disaggregate cell clumps
Vortex the vial 1 minute at maximum speed to disaggregate cell clumps. See [break-up-clumps-and-chains](https://help.sbtinstruments.com/protocols/prepare-your-sample/break-up-clumps-and-chains "mention") if your bacterium needs more aggressive disaggregation.
{% endstep %}
{% step %}
### Dilute 1:100
Transfer 101 µL of your sample to 10 mL of diluent. Vortex 10 seconds at maximum speed.
{% endstep %}
{% step %}
### Dilute 1:10 000
Transfer 101 µL of the diluted sample to 10 mL of diluent. Vortex 10 seconds at maximum speed.
{% endstep %}
{% step %}
### Measure the diluted sample on BactoBox®
Transfer the tubing kit to the 1:10 000 vial.
Press Measure in Access to start a new measurement.
* Dilution: 10 000
* Label: overnight\_-7 , overnight\_-6 , overnight\_-5 or overnight\_-4 ,
After completing the measurement, Access will automatically calculate the bacterial concentration in the cryo stock in the field Cells/mL × Dil.
{% endstep %}
{% step %}
### Check remaining cultures
Repeat above steps with 1:10 000 dilutions of the remaining cultures, in this case vial -6, -5, and -4.
{% endstep %}
{% endstepper %}
## Summary
You have now determined the cell concentration in the relevant cultures. \
Proceed to next step to [choose-best-seeding-ratio](https://help.sbtinstruments.com/protocols/optimize-bioprocesses/identify-optimal-inoculum-size/choose-best-seeding-ratio "mention").
