Either tap water or reverse osmosis (RO) filtered water works well. Once filled, take an EC reading and begin adding nutrients until you reach 1,200 EC above the baseline reading. Then measure and balance pH to 5.8 before planting.

Use a garden hose to make filling easier. Make sure your protective rubber pad is in place beneath the reservoir before filling.

These are the core values to keep your system running well:

No watering 6 to 8 hours before harvest. Use these as your baseline and adjust based on what you observe in your specific grow room.

Target pH is 5.8, with an acceptable range of roughly 5.5 to 6.2. pH tends to drift upward over time due to biological activity in the system, so test and adjust daily.

If pH is out of range, nutrient absorption at the roots is impaired even if nutrients are present in the water. This means pH is almost always the first thing to check when plants show discoloration, slow growth, or any unexplained stress. Fix pH before assuming a nutrient deficiency.

Nutrients are optional for microgreens since their demand is low, and many commercial growers skip them entirely. However, our own production experience over years of growing shows that microgreens watered with a low-concentration nutrient solution grew faster, larger, and were more resilient through the growth cycle.

We recommend MaxiGro 10-5-14, available on Amazon. It is cost-effective, widely available, and dissolves consistently.

• Target EC: approximately 1,200 (measured with a probe)
• Without a digital EC meter: roughly 15mg (1 tbsp) per 20 liters (5 gallons) of water
• Ignore manufacturer concentration recommendations — those are designed for plants grown to full maturity. Microgreens need much less.

We source seeds from two suppliers we trust:

• Johnny's Selected Seeds — excellent variety selection, consistent germination rates, and reliable for commercial growers
• True Leaf Market — strong microgreen-specific catalog, competitive pricing, and bulk options for higher-volume operations

For best results, buy untreated seeds in bulk and store in a cool, dry place. Seed quality directly affects germination rates — old or poorly stored seeds will underperform even in a perfect environment.

Hydroponic systems deliver water and nutrients directly to the root zone on a precise schedule. The result is faster growth, higher yields, and more predictable outcomes than soil-based growing.

• Faster growth cycles — plants grown hydroponically can mature 30 to 50% faster than soil-grown equivalents because they spend less energy searching for water and nutrients
• Higher yield density — no soil means more channels, more plants, and more production in the same footprint
• Consistent results — controlled water, nutrient, and light schedules mean your crops finish the same way every cycle rather than varying with soil composition, weather, or seasonal conditions
• Lower operating cost — reusable mats replace soil entirely, eliminating a recurring expense that compounds over time
• Better food safety — a clean, soil-free environment reduces contamination risk and makes sanitation between cycles fast and straightforward
• Year-round production — indoor controlled environment means you are not dependent on seasons, weather, or outdoor conditions

Hydroponics requires upfront investment and learning, but the output per square foot and per labor hour is substantially higher than any soil-based approach at commercial scale.

When moving planted channels, hold them as level as possible and support the underside. Gripping the drain endcap with one hand while the other supports underneath prevents tipping water and disturbing seeds.

The recommended germination temperature is 65 to 83°F (18 to 28°C). Most common varieties germinate within 72 hours. Keep a thermometer and hygrometer sensor near the rack and check high and low readings overnight and throughout the day.

The most common germination failures and their causes:

• Heat above 85°F (29.5°C) — the most common problem. Equipment heat buildup in enclosed grow rooms is the usual culprit. It prevents germination and can kill newly sprouted seedlings.
• Direct air movement on germinating channels — fans, heaters, or air conditioners aimed at the drain end of covered channels cause excessive evaporation and dry out the channels before germination completes
• Improper planting water pH — often overlooked. If water pH was off during soaking or planting, germination rates will be affected regardless of temperature
• Old or poorly stored seeds — seed quality directly affects germination. Even a perfect environment cannot save bad seeds

If your readings are within the recommended range and your water pH was correct at planting, there is typically nothing to do during germination. The system handles itself.

Look for the seed shell cracking open and white fibrous roots emerging. Uncover channels when most seedlings have begun extending stems upward, reaching for light.

Do not wait too long. If left covered, stems grow excessively long and become leggy plants that cannot support themselves under lights. After uncovering, protect young seedlings from temperature extremes and direct air movement — they need time to acclimate.

Before placing uncovered channels under lights, install drain wicks beneath the grow mat and through the drain. The wick should extend a few inches out the drain spout but should not touch the drain. This prevents standing water from accumulating under the mat during the growing phase.

This is one of the most common concerns for new growers, and the two are easy to tell apart.

Healthy root hairs radiate outward from the white main root structure in an organized pattern. If you spray them with water, root hairs will flatten and disappear into the root mass.

Mold spreads throughout stems or across the surface of the growing substrate in a disorganized pattern. Mold will NOT disappear when sprayed with water.

If you do have mold during germination, the likely causes are unsanitized equipment or channels, excessive heat in the grow room, or stagnant air from covers left on too long. Reduce moisture, improve airflow, and investigate before the next planting.

Soil introduces variability at every step. Packing density, moisture retention, and nutrient distribution all vary batch to batch. Our reusable grow mats eliminate that variability entirely.

• Even moisture distribution — the mat absorbs and holds water consistently across the full growing surface, reducing dry spots, oversaturation, and uneven growth
• Stable root support — plants anchor into the mat structure consistently, which leads to more uniform growth and denser canopies
• No soil disposal — after harvest, roots pull out cleanly. Rinse the mat, let it dry, and it is ready the same day
• 70 plus cycles per mat — at $9.95 to $28.65 per mat depending on size, your cost per cycle drops to cents after the first handful of uses
• Eliminates soil cost entirely — no soil purchasing, no tray disposal, no variable media quality from supplier to supplier
• Better food safety — a smooth, soil-free surface is easier to sanitize between cycles and dramatically reduces the risk of pathogen carryover

The 9"x30" mat is designed for StarterKit and AutoKit channels. The 9"x72" mat is designed for Commercial Production Rack channels. The 10"x20" mat is a direct replacement for standard soil trays.

Hydroponic grow rooms naturally become very humid due to aerated water and high plant density. Without control measures, relative humidity can exceed 90%. Target 40 to 60%.

Humidity control strategies:

• Use box fans or oscillating fans to encourage air circulation throughout the space
• Install exhaust fans to exchange air with the external environment when outside air is less humid
• For larger operations, invest in a high-capacity dehumidifier — more efficient units save energy over time
• Increase fan speed as plants grow larger and the canopy densifies

Temperature control strategies:

• In cooler months: increase external air exchange when outside temperatures are lower than inside
• In summer: reverse lighting cycles so lights are OFF during the hottest daytime hours and ON at night
• Insulate your reservoirs — water temperature is more critical than air temperature because warm water holds less dissolved oxygen
• Use water chillers if air temperatures remain excessively high for extended periods
• For year-round control at scale: a dedicated HVAC system is essential. Consult a licensed professional for your specific facility

As water temperature rises, its ability to hold dissolved oxygen decreases. Dissolved oxygen is critical for plant roots to absorb nutrients. Without adequate oxygen at the root zone, nutrient uptake stalls even if your EC and pH are correct.

Higher water temperatures also increase the risk of waterborne pathogens multiplying in the reservoir. Target water temperature: 68 to 72°F (20 to 22°C).

To maintain dissolved oxygen:

• Use submersible stir-pumps or air pumps with airstones to continuously agitate and circulate the water
• There is no risk of over-oxygenating your reservoir — more agitation is always better
• Insulate reservoirs to slow temperature rise in warm environments
• Use a water chiller if air temperatures in your facility regularly exceed safe ranges

Water has high specific heat capacity, meaning it changes temperature slowly. This is an advantage — your reservoir will not heat up as fast as your air temperature. But if air remains excessively hot for extended periods, water temperature will eventually follow.

Leaf discoloration has several possible causes. Work through them in this order before drawing conclusions:

• pH out of range — check this first, every time. pH imbalance blocks nutrient absorption at the roots even when nutrients are present. Most growers who assume a deficiency actually have a pH problem. Correct pH to 5.8 before changing anything else.
• Overwatering — the most common physical cause. Look for water droplets on leaf edges or under the canopy. Reduce watering interval and increase fan airflow.
• Underwatering — look for wilting between water cycles. Increase duration or reduce the interval between waterings.
• Excessive light duration — if pH and water are correct, try shortening the light period slightly.
• Actual nutrient deficiency — only suspect this after ruling out the above. If you are running at 1,200 EC with balanced pH, true deficiency is unlikely in a microgreen cycle.

A practical inspection habit: select a centrally located channel in the rack and spread the greens to inspect the undergrowth at the center of the grow mat. This is the densest region where mold and rot begin, and where the earliest signs of overwatering will appear.

Mold and rot are moisture and airflow problems, not random bad luck. Rot only begins after something has already caused plant death — always investigate what killed the original plants rather than just treating the symptom.

Mold during germination is caused by:

• Unsanitized equipment or channels
• Excessive heat in the grow room (above 85°F)
• Stagnant air or moisture from covers left on too long

Fix for mold and rot during growing:

• Reduce watering frequency and duration immediately
• Increase fan airflow on and around the affected channels
• Reduce ambient humidity using air exchange or dehumidifiers
• Review seed density — overcrowded plantings create canopies that trap moisture at the mat surface and accelerate the spread of rot

Seed density matters more than most growers expect. The denser the planting, the faster a small patch of dead plants creates a domino effect on surrounding plants. When you find dead patches, inspect seed density on adjacent channels and adjust your next planting accordingly.

Reduce or eliminate watering in the 6 to 8 hours before harvest. Excess moisture in harvested greens diminishes product appearance, quality, and dramatically shortens shelf life. This is one of the highest-impact pre-harvest steps.

Harvest day checklist:

• Unplug or disable your pump and timer to prevent accidental watering during harvest
• Check channels for moisture indicators: dripping wicks, moisture visible in the leaves, or water pooled under the grow mat
• Confirm harvest containers, tools, and cooler space are clean and ready before you cut a single channel
• Plan your harvest order — harvest the most sensitive varieties first to get them into the cooler quickly
• Make sure your harvest trimmer battery is fully charged before you start

Always store greens below 41°F (5°C). The ideal cooler temperature is 32 to 36°F (0 to 2°C).

Post-harvest storage routine:

• Cover harvest containers with breathable white linen napkins initially. This allows moisture to release and greens to crisp up without over-drying.
• After an appropriate crisping period, replace the linen with a solid plastic lid.
• Monitor greens regularly. Too much time under a breathable cover will cause them to release too much moisture and wilt.
• Keep your cooler clean, with condensers draining efficiently and low internal humidity.

The single biggest shelf life killer is excess moisture at harvest. Greens that were watered in the hours before cutting will not crisp up properly in the cooler and will deteriorate faster. Pre-harvest dry-down is not optional — it is the foundation of product quality.

Battery-operated hedge trimmers are the recommended harvest tool. They provide the best balance of harvest speed, cut quality, and control. Key notes:

• Charge batteries fully before every harvest — battery life is sufficient for a full harvest session but only if you start fully charged
• The blade can be removed for sanitizing and sharpening
• Apply food-grade lubricant to moving parts after thorough cleanings
• Replace the battery when capacity starts to degrade

For harvest containers, use food-grade plastic storage totes sized to accommodate your typical harvest volume and fit efficiently in your cooler. White linen napkins work well for the initial crisping phase and are easily laundered and reused.

Change reservoir water at least once per quarter (every 3 months). Depending on planting load and varieties, you may need to do it more frequently. The best time is immediately after a harvest so the entire system starts fresh.

Always unplug your pumps before draining. This is the most common mistake that causes pump damage.

Water change procedure:

• Connect drain hose to the threaded fitting on the reservoir bottom, unplug pumps, then open the valve to drain
• Disconnect and remove submersible pumps to a sink for cleaning — rinse the sponge pre-filter and scrub the exterior
• Scrub the drained reservoir interior with diluted bleach solution, then rinse with fresh water
• Reconnect plumbing and refill with fresh water
• Mix nutrients to target EC (1,200 above baseline), then adjust pH to 5.8
• Power pumps back up and reactivate all timers

The most important first step is letting mats dry completely before attempting to clean them. A properly dried mat feels dry and slightly stiff, with plant matter that is crispy — stems snap rather than bend, and root matter flakes away. Attempting to clean a damp mat is significantly harder and less effective.

Drying options:

• Hang in direct sunlight when weather allows — fastest method
• Dry indoors using fans, dehumidifiers, or safely positioned heaters

Cleaning methods by variety type:

• Shop vac with a brush head attachment — works well for most varieties and is low-mess when mats are fully dry
• Masonry hand trowel scraping — for difficult varieties like arugula, use a smooth-edged concrete finishing trowel to scrape plant and root matter from both surfaces. This is highly effective without damaging the mat.

With proper cleaning and drying, our reusable grow mats are rated for 65 to 70 cycles. At that point, the cost per cycle is cents regardless of which mat size you use.

pH probes are the most maintenance-sensitive component in the system. A probe that reads inaccurately will cause you to chase problems that do not exist or miss the ones that do.

• Never let probes dry out — keep them submerged in water or probe storage fluid when not in use. The cap is designed to extend probe life and should be replaced securely after every use.
• Clean probes regularly of accumulated algae or nutrient precipitate
• Calibrate using pH calibration solutions every 1 to 3 months. If readings seem off between scheduled calibrations, recalibrate immediately rather than waiting.
• Handle the glass sensor probe carefully when moving it in and out of the reservoir — glass probes break if dropped or forced

EC probes are less fragile than pH probes but should be rinsed and dried after use and calibrated periodically. If EC readings seem inconsistent, check for mineral buildup on the sensor surface before assuming the probe has failed.

The in-line screen filter is installed on the irrigation feed line to remove particulate matter pulled from the reservoir by the pump. Its purpose is to keep the small feed-line tubes free from blockage.

Check frequency varies by system load and varieties grown. Start by checking once per week. If filters are consistently clean after several weeks, reduce check frequency accordingly. If flow meter readings are lower than expected for your cycle times, clogged in-line filters are the most likely cause.

Critical note: always ensure the line is not carrying water and will not be activated while you have the filter removed. Change the watering timers or unplug the pump before removing any filter. Do not forget to reactivate and replug when finished.

Flow meters run on small batteries. When a battery dies, replace it by unscrewing the flow meter a half turn to expose the back panel and using a flathead screwdriver to quarter-turn the back cover off.

Remove submersible pumps from the reservoir during every water change for cleaning and inspection. This is the correct maintenance cadence — at minimum once per quarter.

Cleaning procedure:

• Remove the protective housing and inspect the impeller for debris
• Remove and rinse the sponge pre-filter — this is what catches debris before it reaches the impeller
• Scrub the exterior of the pump housing and cord
• Run faucet water through the pump body to flush any internal buildup
• Inspect for proper functioning before returning to the reservoir

The stir pump (smaller submersible pump) handles aeration and circulation. The larger pump irrigates your grow channels. Both use the same cleaning approach. If either pump is underperforming, check the pre-filter and housing before assuming the pump has failed — clogged pre-filters are the most common cause of reduced flow.