400-Watt HPS grow lights are the most commonly used HPS grow bulb, covering around 16 square feet and capable of producing high yields. 600-Watt HPS grow lights are the most efficient HPS grow lamp. 600W HPS grow lights produce more light output per Watt used than other wattages and cover around 36 square feet.

How far should a 400 watt HPS be from plants?

For 400W HPS, the best distance from seedlings is between 12 inches or 30.48 cm (closest) and 19 inches or 48.26 cm (furthest). What is this? 400W HPS grow lights are the most commonly used HPS grow bulbs. These lights can cover around 16 square feet and produce high yields.

How many plants can a 400 watt HPS grow?

Yield Lab 400W HPS+MH Air Cool Hood Reflector Grow Light Kit (Price: $189.95) — A 400w HPS light provides 55,000 lumens, while a 400w MH light generates 36,000 lumens. This light intensity is enough to provide coverage for 1 to 2 plants.

How much can a 400 watt HPS yield?

400 watts of an HPS grow light could lead to 400 grams (14 ounces) of weed at the end of the day. 1200 watts would lead to 1.2 kilos (42 ounces) of marijuana, etc.

How high should HPS be?

HPS lights should not be placed inches from the plants, as you would place fluorescent lights; you should set HPS lamps higher, generally between 5 and 8 feet from the plants. Whether you have a reflector with your HPS light makes a difference for how close you can keep it from the plants.

Whats better HPS or LED grow lights?

LED grow lights are more energy efficient. They produce the same amount of light as HPS lights but consume substantially less energy. LED grow lights do not produce as much heat as HPS lights, avoiding the need for additional ventilation or airflow systems.

What is better for veg MH or HPS?

Ironically, most HID grow light enthusiasts recommend using both MH and HPS grow lights. MH grow lights (metal halide) are suited best for vegetative growth and HPS grow lights are superior for flowering.

How much can a 600W HPS yield?

If someone catches you, you only have four plants to your name. Either way, growing four plants using a 600-watt HPS lamp could produce about 150 grams or 5.0 oz per plant. Sixteen plants that are grown under a 600-watt HPS lamp could produce about 37.5 grams or 1.3 oz of marijuana per plant.

How many plants can I fit in a 4x4 grow tent?

Answer: Putting 6 plants in a 4×4 grow tent leads us to a plant density of 1 plant in each meter square area. That’s a pruning style growing, from where you can expect about . 25 lbs of harvest from each plant.

How much heat does a 600W HPS take?

If you have a 600 Watt HPS lamp, the BTUs for that luminaire are the same as a 600 Watt LED. A single watt of power is equal to 3.41 BTUs so a 600W luminaire will produce 2,046 BTUs.

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How far away should my lights be during flower?

During the flowering stage LED Grow lights should be located between 16-36 inches from the plant canopy. Moving the grow light closer will increase the light intensity which can maximize photosynthesis.

How close do grow lights need to be to house plants?

Fluorescents should be at least one foot away from your plants, so as your plant grows be sure to adjust the height of the grow light. LED lights give off almost no heat at all, so it’s safe for houseplants to grow within 6 inches of them.

Can you veg under a HPS?

In response to the general question, can you use an HPS bulb for veg, the answer is yes. … Basically you can use just about any light out there for any stage of growth, the real question is how well do each bulb work for veg.

Can you replace a high pressure sodium bulb with a metal halide?

Both Metal Halide and High Pressure Sodium bulbs are part of the HID family of bulbs. … These bulbs cannot be interchanged without changing their ballast, the regulating element in all light bulbs. Their operation is a bit different and they therefore require different ballasts.

What's the best HPS grow bulb?

As a general rule, 400w HPS bulbs are the most common, 600w HPS bulbs are the most efficient, and 1000w HPS bulbs are the most powerful (but also the hottest).

Can I switching from HPS to LED during flowering?

LEDs Provide a Higher Quality Light Spectrum There was a time when switching from MH to HPS bulbs between veg and flower counted as tailoring your light spectrum to your plants’ needs. … When you switch from HPS to LED, your plants receive the blue hues they need for sturdy growth and root development.

What's better HPS or metal halide?

HPS is about twice as electrically efficient as metal halide. Photosynthetically Active Radiation (PAR) is what really matters to plant growth, and delivery of usable PAR is better with HPS than metal halide. … Metal halides deliver, on average, about 80,000-110,000 lumens per standard 1,000-watt bulb.

What is the McCree curve?

The McCree curve describes the quantum efficiency of photosynthesis at different wavelengths at low light. The action spectrum describes actual photosynthetic rates and thus is the curve on which to base spectral selections.

Can you use HPS lights in a grow tent?

All You Need to Know About HPS (High Pressure Sodium Lights) For Growing. High-pressure sodium lights are a good choice because they emit a light that is stronger in the orange / red spectrum, due to their rich sodium content. Growing a young plant with HPS bulbs will ensure an impressive vertical growth.

Can you use HPS and LED together?

The way HPS lighting should be installed is so that the light overlaps so shadows are reduced, and light penetrates in a horizontal direction. Having a mix of both HPS and LED lighting provides an ideal distribution of both diffuse and directional light.

How long do HPS lights last?

Typical lifespan values for an HPS bulb are around 24,000 hours. According to American Electric Lighting, “HPS lamps still generate 90% of their initial light output at the midpoint of their life span.

Can I put a dehumidifier in my grow tent?

The answer is simple. You can place dehumidifiers both outside and inside grow tent.

Do you have to have a fan in a grow tent?

They blow air constantly above, under, and around your plants, helping to keep the grow room cool and improve air circulation. … You need an air extractor fan system to keep the air in your grow room or grow tent fresh.

What size tent do I need for 4 plants?

What Size Grow Tent Is Best For 4 Plants? For 4 plants, a rectangular tent shape is best and the most common size is a 4×4. That gives each plant about 4 square feet of growing space (a 2×2 area). It is actually a bit less than that, because you want to keep some space free between the plants.

How many HPS watts for 4x4 grow tent?

600w HPS Grow Lights — Great for 4×4 Areas 600w grow lights are the perfect option for 4x4ft grow tents and grow rooms. They offer 90,000 lumens, making them ideal for helping at least 2 to 3 flowering plants thrive.

How many plants can I grow under a 600w LED light?

2 month plants should give about 40g per plant, so with about 9 you’ll be able to easily fill a square meter and get up to 400g per 600w light. 3 month autoflowering plants grow much bigger, however, so you should only plant 4 per 600w light.

How much does it cost to run a 600 watt grow light?

The cost to run the lights per day is $0.2735236 or $8.20 per month. If I have an HID (high intensity discharge) light with a 600 watt bulb in it, using the same method of calculation, it would cost me $30.90 per month.

How much heat does a 400 watt metal halide produce?

For instance a 400 Watt Metal Halide High Bay lamp puts off 1,364 BTUs per hour vs. a 150 Watt LED High Bay puts off 511 BTUs/hr.

Are LED lights cooler than HPS?

One of the biggest differences between LEDs and HPS is radiant heat. … Also, the HPS will deliver approximately 34% of that energy in the visible light wavelength, while the LED will deliver 40-50% of it’s BTU energy as visible light (and is why the LED is more efficient).

How do I keep my HPS light cool?

Air-cool the lamps. Directly cool your lamps with a separate ventilation system. Use a sealed hood for your lighting and run additional ducting to directly cool the lamps (as a bonus, place dry ice above your lamps to help cool them and add CO2 to your grow room).

Can I use a 1000 watt bulb in a 400 watt ballast?

You can do it with a 1000w bulb with a 400w ballast but not the other way round. Use the correct bulb with ballast. 1000w’s of electric is a lot to be playing about with and it will explode if you get it wrong or cause heat problems.