Preseason Checklist: Getting Your Facility Ready Before First Landing
There's a version of spring startup that goes well: you work through the system methodically in March and early April, fix the two or three things that need fixing, and by the time the first truck rolls in you're ready. There's another version that doesn't — and it involves discovering a seized chiller compressor at 9 PM on your first big landing day.
The difference is almost always preparation. The time to find problems is before 50,000 lbs of lobster shows up at the dock. Here's a structured startup checklist with explanation for each item. Work through it in order, and plan to be done at least two weeks before your anticipated first landing.
Flush and Clean the System
Drain tanks, sumps, and flush all piping
Any standing water left over winter is a contamination risk. Drain completely, inspect for cracks and sediment, then run fresh water through the full pipe circuit. Check all low points where debris can settle. Clean plate heat exchangers now — fouled plates reduce thermal efficiency significantly. A heat exchanger at 60% efficiency is costing you in both energy and temperature control.
Chiller Commissioning
Verify refrigerant charge and inspect the compressor
Refrigerant loss over winter is one of the most common reasons chillers underperform at startup. Even a small leak can drop cooling capacity by 20–30%. Check suction and discharge pressures against manufacturer specs. Inspect compressor oil level and condition, and check condenser fins — bent fins restrict airflow and hurt efficiency.
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Run the chiller unloaded before connecting to the system
Start the chiller on bypass and run it for 30–60 minutes before putting load on it. Verify it reaches setpoint, listen for unusual sounds, and watch the pressures. If there's a problem, you want to know now — with nothing in the tanks — not at 2 AM with product at risk.
Biofilter Seeding — Start 4 to 6 Weeks Early
Assess media condition and re-establish the biofilm
This is the most time-sensitive item on this list. Nitrifying bacteria — which convert toxic ammonia to harmless nitrate — are slow-growing. A biofilter that's been dormant over winter may have lost the majority of its active biomass. Reestablishing a stable biofilm takes 4 to 8 weeks. Put full load on an unestablished biofilter and you'll get an ammonia spike that can persist for days. Seed using ammonia dosing (ammonium chloride at 1–2 mg/L TAN) or by running a small number of animals through the filter. Keep it aerated and running continuously — do not let it go anoxic during the seeding period.
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Verify aeration to the biofilter
Nitrification requires dissolved oxygen. Confirm all diffusers are functioning. DO in the biofilter zone should stay above 4 mg/L — below 3 mg/L, nitrification efficiency drops sharply. On MBBR systems, verify that media is moving freely; stationary media indicates a diffuser problem.
Pump, Plumbing, and Flow Verification
Inspect pump seals, impellers, and all valves
Check pump seals for signs of seepage — water staining around the housing is the tell. Spin impellers by hand and listen for grinding. Operate every gate valve and ball valve to confirm they seat fully; a valve that sticks is a problem during an emergency when you need to isolate a tank fast. PVC fittings stressed over the season can develop micro-cracks that only show under pressure — walk the system with the pumps running.
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Verify and balance flow rates
Use a bucket and stopwatch to confirm each tank is receiving the intended flow. Unbalanced systems leave some tanks under-supplied on water exchange while others waste chilled water. If you have flow meters, verify calibration — float-type meters in particular can stick after sitting idle.
Sensor Calibration
Calibrate DO and temperature probes
DO probes drift over time. Membrane-type polarographic probes may need membrane replacement; optical sensors still need a calibration check. An uncalibrated DO probe showing 8 mg/L when the actual reading is 4 mg/L is worse than having no probe — you'll miss a dangerous condition entirely. Verify temperature sensors against a reference thermometer at two points and replace any that read more than 0.5°F off. If you use pH probes, calibrate with fresh buffer solutions — not last season's partially evaporated bottles.
Water Quality Baseline
Test water chemistry before loading any animals
Before any animals go in, run full water chemistry: TAN, nitrite, nitrate, pH, alkalinity, salinity, and dissolved oxygen. Document the numbers — they're your baseline for comparing against once you start loading. If ammonia is elevated before animals arrive, you have a problem to solve before startup, not after. If you're using municipal water, dechlorinate before adding to the biofilter; chlorine kills nitrifying bacteria.
Pre-Season Test Run
Run at 20–30% load for one week before first landing
If possible, bring in 5,000–10,000 lbs of animals and run them through the full system for a week before your main season starts. This validates that everything works together under real conditions, confirms the biofilter is properly established, and surfaces integration problems that aren't visible during idle commissioning. It also gives your staff a chance to work out the off-season rust before the real pressure begins.
Build Your Facility-Specific List
This checklist covers the baseline. Every facility has its own quirks — the pump that always gives trouble in May, the section of pipe that needs watching after a cold winter. Add those items to your own checklist alongside these. The goal is simple: no surprises during season.
If your facility needs a systematic preseason review or you're commissioning new equipment, Aqua Production Systems can help. We work with live seafood holding operations throughout Atlantic Canada and beyond. Visit aquaproduction.ca or give us a call.