Description
Set the Humidity You Want and Let the Humidifier Hold It
The Spider Farmer 5L Smart Cool Mist Humidifier is an ultrasonic humidifier for grow tents and small grow rooms. Its built-in humidistat reads a supplied sensor on a 2.5 m lead and mists only when the air falls below your target, anywhere from 35% to 95% RH. Four mist levels give 180 to 450 ml/h, and twin hoses spread the mist across the canopy.
Key Benefits
- Automatic humidity control - set a target between 35% and 95% in 5% steps and the unit cycles itself to hold it
- Four mist levels - 180, 270, 360 or 450 ml/h to suit anything from a propagation tent to a 150 cm tent
- Long run from one fill - the 5 litre tank lasts roughly 11 hours on full output and nearly 28 hours on the lowest
- Mist where the plants are - extendable hoses (one 45-180 cm, two 18-62 cm) and a Y-splitter reach both sides of the tent
- Quiet and safe - about 30 dB, 30W, with a low-water alarm and automatic shut-off
- App control with GGS - connect to a Spider Farmer GGS controller or power strip by RJ12 cable for remote control and schedules
Is Dry Air Holding Back Your Plants?
Grow lights, heaters and extraction all dry the air, and in winter a tent can sit well below the humidity that seedlings, cuttings and leafy plants need. Plants then lose water faster than the roots can replace it: leaves curl, growth slows and nutrient uptake suffers. Holding humidity steady keeps transpiration in balance and eases transplant shock and early root development.
How to Use
- Fill the tank from the top or lift it off the base. Spider Farmer recommends distilled water to limit mineral build-up; never pour water into the mist outlet.
- Fit the hose and hang it in the tent with the supplied straps, with the outlet angled slightly upwards. Do not bend or kink it, or condensed water collects and drips.
- Hang the sensor at canopy height and set your target humidity and mist level on the control dial.
- Use the timer (1-24 hours) if you want it to switch off after a set time.
- Keep it clean - change the water at least every four days and clean the base weekly with distilled water and a little vinegar, brushing the nebuliser.
Technical Specifications
- Model: Spider Farmer SF-Humidifier5 (2026 version, SF-Humidifier5-260305)
- Type: ultrasonic cool mist humidifier with built-in humidistat
- Tank capacity: 5 litres
- Mist output: 4 levels: 180, 270, 360 and 450 ml/h (max 450 ml/h ±5%)
- Humidity setting: 35-95% RH in 5% steps
- Timer: 1-24 hours
- Power: 30W ±5%, AC 100-240V, 50/60Hz, 2.5m power cord
- Noise: 30dB or less
- Size and weight: 21 x 21 x 30.4cm, 1.88kg
- Sensor: temperature, humidity and light (day/night) sensor on a 2.5m cable
- In the box: humidifier, 45-180cm hose, two 18-62cm hoses, 2-way nozzle, sensor probe, RJ12 cable, waterproof connector, 3 straps, tool bag
- Safety: low-water alarm with automatic shut-off
- Smart control: with a Spider Farmer GGS controller or GGS power strip kit (sold separately)
- Warranty: 2 years (manufacturer)
Frequently Asked Questions
Does it need a Spider Farmer controller to work?
No. Its own humidistat and the supplied sensor hold the humidity you set, from 35% to 95%. A GGS controller or GGS power strip only adds app control and scheduling; once connected, the app takes over the humidity setting.
How long does a full tank last?
About 11 hours at the top setting of 450 ml/h and nearly 28 hours at the lowest, 180 ml/h. On humidistat control it only runs when needed, so a fill usually lasts longer.
What water should I use?
Spider Farmer recommends distilled water, which keeps scale off the nebuliser and stops white mineral dust settling on leaves. Change the water at least every four days.
Can the humidifier stand outside the tent?
Yes. Stand it outside and run the hose in through a port, hung so the outlet points slightly upwards and the hose has no sags or sharp bends for water to collect in.
Works Well With
