Why pre-screen algaculture technicians before the interview
Cultures crash quickly and usually over a weekend. Contamination by a competing organism, a pH excursion, light or temperature drifting outside range: any of these can end a run, and the early signs are subtle in a green tank. Technicians worth hiring measure daily and keep records that let a crash be traced. A short screen asks about a culture they lost.
What actually matters when screening Algaculture Technician candidates
- 01
Technique and experimental design
Check hands-on command of strain scale-up from agar slant to flask to photobioreactor: media recipes (f/2, BG-11), sterile inoculation, light and CO2 dosing, salinity and pH setpoints.
- 02
Results that went somewhere
Probe production numbers they owned: grams per litre per day, harvest volumes, lipid or protein content, contamination-free run length, and what the biomass was sold or processed into.
- 03
Troubleshooting and reproducibility
Test response to crashing cultures: rotifer or ciliate grazers, cyanobacterial contamination, photoinhibition, biofilm on tube walls, chiller failure, and how they diagnosed rather than guessed.
- 04
Documentation and collaboration
Assess record keeping: daily culture logs, haemocytometer or Coulter counts, optical density readings, batch traceability, plus handovers to harvest, downstream processing, or R and D staff.
Pre-screening questions to ask Algaculture Technician candidates
12 questions grouped by what they test. Ask the same set in every screen and score answers on a consistent scale, or send them as an async video screen and compare answers side by side.
Systems they ran
3 questions01Do you have previous experience in algae or aquatic cultivation?
Listen forHands-on operating time with the species and system type named, and their daily duties described.
Experience described academically, or no responsibility for running cultures day to day.
02Do you have experience with commercial-scale cultivation systems?
Listen forProduction scale operated with volumes stated, and the difference from laboratory work understood.
Only flask or small vessel work, or production scale challenges unfamiliar.
03Can you detail your experience with closed reactors and open pond systems?
Listen forBoth understood with the contamination and control trade-offs between them described accurately.
One system type known only, or the contamination risk of open systems underestimated.
Monitors closely
4 questions04How do you monitor and measure algae growth?
Listen forCell density, pH and temperature measured daily with results logged and trends watched.
Growth judged by colour, or measurements taken only when something looks wrong.
05Can you describe troubleshooting a difficult problem in a cultivation setting?
Listen forA crash or contamination traced through records to a cause, with the process changed afterwards.
Failed cultures discarded and restarted, or causes never identified from the data.
06Do you have experience identifying algae species and contaminants?
Listen forMicroscopy used routinely to spot competing organisms and grazers before they take over.
Contamination noticed only when the culture fails, or microscopy never performed.
07What knowledge do you have of strain selection for cultivation?
Listen forStrains chosen for productivity and robustness in the actual conditions, not laboratory performance.
Strain chosen on published yields alone, or local conditions not considered in selection.
Harvest preserves value
2 questions08Are you familiar with harvesting and processing algae?
Listen forHarvest timed to condition, with dewatering and drying handled to protect the target product.
Harvest timed by schedule alone, or processing delays that degrade the product quality.
09What experience do you have maintaining cultivation equipment?
Listen forPumps, sensors and lighting maintained on schedule, with cleaning between runs done thoroughly.
Maintenance done reactively, or cleaning between batches treated as optional.
Safety and records
3 questions10How do you implement safety practices in this setting?
Listen forSlip, electrical and confined space hazards recognised around wet tanks and equipment.
Safety described generally, or the combination of water and electricity not treated seriously.
11How comfortable are you handling the chemicals used in this process?
Listen forNutrients, acids and cleaning agents handled with protection, and incompatible products separated.
Concentrates handled without protection, or cleaning chemicals mixed without checking.
12Do you have experience maintaining production and growth records?
Listen forRecords kept daily and completely, so a failed batch can be reconstructed and understood.
Records completed retrospectively, or gaps in the log during busy periods.
How to score responses
Score every candidate on the same four criteria immediately after the screen. At this stage you are shortlisting for panel interviews, not making the final call.
Technique and experimental design
35%5Names strains grown (Nannochloropsis, Spirulina, Chlorella), recites media formulations from memory, and explains why each scale-up step ratio was chosen.
Results that went somewhere
25%5Quotes actual productivity and harvest yields across seasons, and links a process change to a measurable gain in biomass or purity.
Troubleshooting and reproducibility
25%5Walks through a real crash using cell counts, microscopy, and DO or pH trend data, then names the corrective action and prevention step.
Documentation and collaboration
15%5Keeps disciplined batch records others can reconstruct, flags anomalies same shift, and coordinates cleanly with harvesting and quality teams.
Cultures crash quickly and usually over a weekend. A one-way video screen asks about the one they lost.
Try it on HirevireScreening FAQ
Process basics
How long should a pre-screening round for this role take?
Ten to fifteen minutes across eight to ten questions, answered async. Enough to establish systems they ran, test their monitoring discipline, and check harvest and safety practice.
Does open pond or closed system experience matter?
Yes, they behave differently. Closed photobioreactors allow tighter control and cost more; open ponds are cheaper and far harder to keep free of competing organisms.
Evaluating answers
What is the strongest signal when screening this role?
A culture they lost and why. Technicians with real operating time have one and can trace the cause through their records. Anyone whose cultures never crashed has not run many.
How do I judge their monitoring discipline?
Ask what they measure daily. Real answers include cell density, pH and temperature with a log kept. Anyone assessing culture health by colour will notice a crash too late.
Go deeper on this role
Sanat has been hiring since 2012 and watching the recruitment industry change up close ever since, and turned that screening process into Hirevire's video screening platform. LinkedIn
