Going with Gavitas but need some advice

[PeterWB]

I am setting up a new grow room that will be used entirely for flowering. Vegging is done in a separate room. I have purchased 9 Gavita Pro 1000 DE US as I have heard that they are the best lights around. My room is 24 by 24 and I will have a 2 foot aisle around the perimeter and two more 2 foot aisles running between three hydroponic setups of 30 plants each. My ceiling height is a little over 7 feet and the buckets are one foot tall.

I've perform the lighting calculations using various methods and am worried I don't have enough lighting. 9,000 watt for 90 plants seems fine but some of the lighting calculators would have me running for more lights.

Any help is appreciated.

 

[Lifer]

I run the DEs over a minimum of 3.75x3.75' and maximum of 5x5'. You'll probably get better performance with the DE running at 1150w and 24-36" away from canopy than you're used to getting with 1kw air cooled hoods from 18-24".

Shoot for 3LB+ if you're burning gas, 2+ is easy even without gas.

Peace

 

[PeterWB]

I run the DEs over a minimum of 3.75x3.75' and maximum of 5x5'. You'll probably get better performance with the DE running at 1150w and 24-36" away from canopy than you're used to getting with 1kw air cooled hoods from 18-24".

Shoot for 3LB+ if you're burning gas, 2+ is easy even without gas.

Peace

Is that 3lb per plant

 

[Skyrancher]

I am setting up a new grow room that will be used entirely for flowering. Vegging is done in a separate room. I have purchased 9 Gavita Pro 1000 DE US as I have heard that they are the best lights around. My room is 24 by 24 and I will have a 2 foot aisle around the perimeter and two more 2 foot aisles running between three hydroponic setups of 30 plants each. My ceiling height is a little over 7 feet and the buckets are one foot tall.

I've perform the lighting calculations using various methods and am worried I don't have enough lighting. 9,000 watt for 90 plants seems fine but some of the lighting calculators would have me running for more lights.

Any help is appreciated.

From what DHF and others suggest, the magic lighting number is 50w per square foot, although with Gavita's, you'll have the benefit of over-lapping light to help out, which may lower that number some.

With your 2' perimeter, your grow area is 20'x 20' = 400 sq ft

Using 9000w of light, gives 9000/400 = 22.5w per sq ft.

You could put your tables on rollers, which would allow you close up the inner 2 foot walkways when not doing maintance? Subtract for two 2' walkways in the middle would be 16'x 16'?

9000/256 = 35w per sq ft.....still short I think.

I suggest finding Whazzup here on ICMag. Read his posts and/or send him a PM. He is the Gavita pro !! He talks about lighting "a room, not trays" (or individual areas), to get the best use of over-lapping light possible. Your walkways, although nessessary for maintance, cut the efficency of the Gavita lighting system. Give Whazzup a shout. He seems very helpful and extremely knowledgable about Gavita. He may find your thread as well.

Good luck

 

[Johnny Redthumb]

high yield is in the light overlap for sure. that being said, less is often more and since you don't have much ceiling height, start with 9 lights. you can always add more later! good luck with the gavitas...they rock!

 

[PeterWB]

I considered rollers but not sure they are practical when growing hydroponically. I am considering dedicating one third of the room to soil, so maybe I could make the rolling tables and add more lights.Obviously the table needs to be very low to the ground. Thinking 4' x 4' 2x4 structure with plywood would do the trick.

I'll send Whazzup a PM for sure.

 

[Stonefree69]

From what DHF and others suggest, the magic lighting number is 50w per square foot, although with Gavita's, you'll have the benefit of over-lapping light to help out, which may lower that number some.

With your 2' perimeter, your grow area is 20'x 20' = 400 sq ft

Using 9000w of light, gives 9000/400 = 22.5w per sq ft.

You could put your tables on rollers, which would allow you close up the inner 2 foot walkways when not doing maintance? Subtract for two 2' walkways in the middle would be 16'x 16'?

9000/256 = 35w per sq ft.....still short I think.

I suggest finding Whazzup here on ICMag. Read his posts and/or send him a PM. He is the Gavita pro !! He talks about lighting "a room, not trays" (or individual areas), to get the best use of over-lapping light possible. Your walkways, although nessessary for maintance, cut the efficency of the Gavita lighting system. Give Whazzup a shout. He seems very helpful and extremely knowledgable about Gavita. He may find your thread as well.

Good luck

Yeah that! Just go by the 50 watts per sq ft rule for decent buds and yield. You can adjust the extra 10-15% output of the lights (about 6.5% for Gavita SE) from whazzup's Ulbricht sphere PAR test (PPF) of several popular 1000W lamps thread:

That's PAR output being measured and you can convert the PAR outputs of different bulbs to watts in a 1:1 ratio. So instead of having 9,000 watts it's like having 9,000 watts + say 10% more or 9,900 watts. And 9,900 watts divided by 50 watts/sq ft gives you 198 sq ft to work with to illuminate your plants under. How many plants you want to grow and how long you want to veg is up to you for that space. Horizontal is great for veg and I like bare bulb vertical for flower.

 

[Kcar]

You're not taking into account that the lights will be over the plants, not lighting
the isles and walkways.

 

[Kcar]

Ok, stoned. I reread and you're all about overlap with the Gavitas.
I've always done two 1k's over a 4x8 tray with space around them for upkeep...

 

[Stonefree69]

Ok, stoned. I reread and you're all about overlap with the Gavitas.
I've always done two 1k's over a 4x8 tray with space around them for upkeep...

Correct. Or another way to work it out going directly from PAR, multiply the watts by efficacy in umol/watt - so 1,000 watts times 2.07 umol/watt gives you 2,070 total umol/sec (micromoles/sec) per lamp.

"To gain a better understanding of the range of PAR values found in nature, I further experimented with my meter by taking readings outdoors in areas where healthy plants were thriving. At noon on a sunny day, I found flowering plants growing in areas where the PAR readings were in the range of 800-1750 umol/m2/s . In partially shaded areas, I measured 300-600 umol/m2/s. And in full shade, the PAR readings were 60-200 umol/m2/s." from http://www.inda-gro.com/pdf/aquarium-lighting.pdf

Also: "In the middle of the day it is possible to arrive at a reasonable equivalence between PAR (PPFD) and Total Energy as measured by a pyranometer. At mid day the maximum PAR value is about 1800 umol/m2/sec and this relates to about 1000W/m2 or 1000J/m2/sec. From this you can derive that 1J/m2/sec is roughly equivalent to 1.8 umol/m2/sec." from http://www.autogrow.com/general-info/light-measurement

So say as a guide I want 900 umol/m2/sec or about 500 watts/m2 (half sun or average throughout the day). 2,070 times 9 gives you 18,630 umol/sec total PAR output. 18,630/900 umol/m2/sec gives 20.7 m2 (square meters) canopy area to work with or that comes out to 223 sq ft (10.76 sq ft in 1 sq meter).

This is still close in results to the 50 watts/sq ft rule which came out to 198 sq ft in my post above. If I wanted 1,000 umol/m2/sec instead of 900 umol/m2/sec output I would have about 200.5 sq ft canopy area to work with. Seems you might be safe with up to 225-250 sq ft, I'd make sure your using something like reflectix and/or Orca grow film to max out that PAR that's reflected back into grow.

 

[CulturedHeathen]

I see that you have a limited vertical space in your setup... with a 7ft ceiling, 1ft hydro setup, MINIMUM 2.5 ft between bulb and canopy and room for the light setup, the plants can be no taller than 2.5ft. Just something to keep in mind. I have a 10ft ceiling and have come close to having plants get light bleaching. If you plan to run the ballasts at 1150w mode, 3ft would be a minimum bringing your MAX plant height to 2'. A/C hoods and standard digi ballasts might be better for your setup.

 

[Stonefree69]

I see that you have a limited vertical space in your setup... with a 7ft ceiling, 1ft hydro setup, MINIMUM 2.5 ft between bulb and canopy and room for the light setup, the plants can be no taller than 2.5ft. Just something to keep in mind. I have a 10ft ceiling and have come close to having plants get light bleaching. If you plan to run the ballasts at 1150w mode, 3ft would be a minimum bringing your MAX plant height to 2'. A/C hoods and standard digi ballasts might be better for your setup.

Interesting. I run vertical bare bulb with 8' ceilings and 16" high 5 gallon buckets. My plants sometimes brush the ceiling and I tie them (lst) using ceiling hooks - so that's 6' 8" maximum plant height. Now that I'm growing more Indica dominants that's plenty height for me vegging 8-9 weeks from seed. PeterWB's room dimensions with vertical lighting and setup plants can hit 6 feet.

Horizontal lighting great for veg and light coverage but when they're taller height restriction is 1 disadvantage.

 

[Incognegro]

I am setting up a new grow room that will be used entirely for flowering. Vegging is done in a separate room. I have purchased 9 Gavita Pro 1000 DE US as I have heard that they are the best lights around. My room is 24 by 24 and I will have a 2 foot aisle around the perimeter and two more 2 foot aisles running between three hydroponic setups of 30 plants each. My ceiling height is a little over 7 feet and the buckets are one foot tall.

I've perform the lighting calculations using various methods and am worried I don't have enough lighting. 9,000 watt for 90 plants seems fine but some of the lighting calculators would have me running for more lights.

Any help is appreciated.

9000 watts is lovely for 90 plants in a vert setup.... but that's just me

 

[CulturedHeathen]

Stone... With the systems he is outlining here (Gavita 1000DE's) Horizontal setup is the only possible format. Given this fact, there are major plant height restrictions in this setup.

 

[Stonefree69]

Stone... With the systems he is outlining here (Gavita 1000DE's) Horizontal setup is the only possible format. Given this fact, there are major plant height restrictions in this setup.

Right and PeterWB said a little over 7 foot ceilings. Those kind of lights I might want a good 24" distance. I generally use 600's but I think a normal distance for 1,000 watt lights is 18-24". The fixture is 13.4" height (from Gavita pdf GAVITA Pro 1000 DE US dimensions).

So reflector + 18-24" canopy distance = about 2.5-3' (31.4"-37.4" precisely). Add in another 1' for bucket height and then subtract that from 7' ceiling gives you a plant height of 3-3.5' to work with (a bit more with slightly over 7' ceiling).

 

[CulturedHeathen]

On the 1000w and 1150 w. settings, Gavita recommends a 3' distance from bulb to canopy... I have 8 of these systems and agree completely with the Gavita reps. These systems are very different than the previous generation of growroom lighting. There are a few threads specific to this topic going on now in the lighting forums. IMO to utilize these systems fully, a 10' ceiling is key.
https://www.icmag.com/ic/showthread.php?t=204324
Wazup is a Gavita rep, I would heed his advice.

 

[PeterWB]

Just as an update, I have built boxes into my ceiling that the Gavitas hang within. The edge of the relector hangs below the standard ceiling by about half an inch. Using central vac tubing I push air from a 6 inch inline fan directly into each light box. I've monitored the temperatures and am happy to find that the temp at the top of the box is only 2 degrees higher than the temperature at mid height in my room. I reconfigured the placement of the lights (light boxes) and plan to have 10 Gavitas 1000 Pro plus one Gavita 300 Plasma. I've changed my hydro configuration so that one third of my room has plants in soil. I'm building 4' x 4' rolling structures to maximize the number of plants in soil.

Just another note: My plants are about 40 days old when they leave my vegging room and are put into the flowering mode. That's the time from taking a cutting to growing a plant between one and two feet tall. I've noticed that I get far less stretch with the Gavitas. I may be able to dedicate more time to veg without worry of the plants getting too big.

 

[Skyrancher]

Good to know you're getting less stretch. That helps. Thinking of going with Gavita Pro 600w 400v remote ballasts vertical bare bulb, for flower and the Gavita LEP 300 for veg. Sounds like you using both HPS and LEP for veg? Is that correct?

 

[hawkwindzoo]

Great lights

 

[PeterWB]

Good to know you're getting less stretch. That helps. Thinking of going with Gavita Pro 600w 400v remote ballasts vertical bare bulb, for flower and the Gavita LEP 300 for veg. Sounds like you using both HPS and LEP for veg? Is that correct?

I'm using one Gavita LEP 300 for veg over an aeroponic system that holds 72 plants in 4" net pots. I'm alos supplementing light with 2 LED high output 4 tube lamps. My plants leave the EZ cloner and go right into the aeroponic veg system. For plant I grow in soil I am strictly using LED lights hung very close to the leaves. I veg for one month and then move plants into my flower room. Everything is very happy.