Gavita or 4 cmh in 5x5 room

Tas devil

Tas devil

Well-Known Member
Hi gents just about to get some fixtures for my first grow..as the title says im tossing up
between the 600/750 de fixture and 4 cmh fixtures.i have been told that i will need to run
an ac between canopy and fixture as my ceiling is only 7ft a liitle less once gav is in there.
Im told the buds will b more dense etc.than the cmh.i want to have an efficient setup and
thinking is it worth running ac as want to keep cost down.i just need some friendly help
and guidance which way to go.im not worried about startup cost .being a newby i want to make it as easy as possible.

Cheers
 
jimihendrix1

jimihendrix1

Well-Known Member
Consider your going to have to have 36-40 inches between the Gavita, and the top of the canopy, leaving 32-36 inches, not including the pot height. Another foot?? Which would then leave 22-26 inches for the plant(s)

At that rate Id get either 2 x 600w CMH, or 2x 600w Hortilux HPS bulbs, or 1 x 1000w Hortilux/HPS.
 
coreywebster

coreywebster

Well-Known Member
Your worst case ambient temps will help you decide on AC or no AC.
How hot is it in summer and for how long?
You can keep good air temps with massive air exchange but you can only be at ambient at best without AC.
AC is very expensive but if its needed its needed.
 
jimihendrix1

jimihendrix1

Well-Known Member
Those lights get hot, and if you don't have really, really good airflow, you WILL have to have AC to keep temps down if its over 60 degrees outside.

Generally it takes 8000btu to cool 1000w. Minimum.
 
W

WaterDog

Well-Known Member
Why not LED?

In your space a Gavita is gonna be a nightmare. I just set one up on a lightrail gonna see how that works but it was wat to hot for my height (8ft)and a 5x5.

I'm a newb but that was my very recent experience. Goodluck
 
Tas devil

Tas devil

Well-Known Member
Thanks for replying guys.its between 3-7 deg celcius overnite and 12 max right now through the day and through aug we will hit zero and a few minus deg nites and sept oct will still b fresh overnite.
It doesnt start warming up to those muggy nites till early jan through to feb.with an average of 13 deg celcius.probably a dozen no more of 20 overnite.summer goes from start nov till end of feb .then we have autumn march which is still warm through the day but nites starting to cool..yeah i worked out what you said Jimi and i think its doable long as i keep the plants short with the ac.and with the el2 controller i can dim the light further or if it gets hot the controller will dim it.
 
Tas devil

Tas devil

Well-Known Member
WaterDog said:
Why not LED?

In your space a Gavita is gonna be a nightmare. I just set one up on a lightrail gonna see how that works but it was wat to hot for my height (8ft)and a 5x5.

I'm a newb but that was my very recent experience. Goodluck
Click to expand...
So am i lol.i love a challenge.is yours a 1000w or 600/750 de 400v
 
Tas devil

Tas devil

Well-Known Member
I think with the 6/750 its 2 1/2 ft to canopy.the cmh are 2 ft..i might b keen on using co2
Later ,that could help as it work as temp can b higher
 
jimihendrix1

jimihendrix1

Well-Known Member
600w Gavita still needs Minimum 36 inches from Canopy. Infrared is Monsterous on these.

For me, in a 5 x 5 area, Id use a 1000w Hortilux HPS. And use 4 x 4 of the area, and use the other 1 x 1 as area to give plenty of space, and not crowed them to much, and for me to move around a bit.

. At 4 x 4 thats 62.5w Sq/ft, and 5 x 5 is 40w sq/ft, though you can use the whole 5 x 5 but the outer edges may be a bit less dense ect. But with good reflection ect, 5 x 5 is good. Hortilux is also 1600 umol (That's what they told me ) at 24 inches, and I can get them considerably closer than that. In the perfect conditions ( WINTER ) I can get 1000w anywhere from 12-20 inches from the canopy, equaling, or bettering a DE Gavita, BUT the Gavita is good for a 5 x 5 area Minimum if standalone, and can be used up to 5 x 6. I also use Gavita 1000w DE. Gavita simply covers more area.

Just like the Hortilux HPS will Blast a 4 x 4, and will work up to 5 x 5 at 24 inches. Gavita will blast 5 x 5 at 36-40 inches, and will work up to 6 x 6.

At that rate, the umol will be very high on the Hortilux at 20 inches.

But bang for the $$$, IMHO you wont beat a 1000w Hortilux/HPS

Bulb is only $65.

If 1 uses CO2, the rom/enclosure has to be 100% AIRTIGHT. Even a pinhole will cause all of the CO2, to go there. It will go to any leak. Id rather just have really, really, really good airflow.

I also have fans constantly blowing on my plants, to strengthens stalks, and stems. I don't beat them to death, but I want every branch in the room, to be moving, so that way I know 100% they are getting some air.I also Bend, Shake,, pull ( Slightly ) on my plants from a young age. I also bend them, and make them grow Horizontally, vs Vertically.

I myself in a 5 x 5 area would be to use wither 4 females in 10 Gallon containers, or 2 plants in 20 Gallon Containers.

I would also expect at LEAST 18oz, but would expect more really. Strain I have now will get 22oz all day in a 20g container/Promix BX x 1000w Hortilux.

In 4 x 4 of the area you would be getting 62.5w in 16 sq/ft, and if 5 x 5 is 40w Sq/ft.
 
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Tas devil

Tas devil

Well-Known Member
Thanks Jimi.what reflector and ballast you using with the hortilux bulb.i see theres a few kinds of bulb to run.
 
jimihendrix1

jimihendrix1

Well-Known Member
Hortilux HPS Superbulb. Comes in 250w, 400w, 600w, and 1000w. High Pressure Sodium

Galaxy Electronic Ballast. 1 around $170.

Magnum XXXL Low Pro Reflector.
 
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Tas devil

Tas devil

Well-Known Member
zypheruk said:
I would suggest 315cmh x 4 for better spread over the canopy and it wont create a massive hotspot in the middle.
Click to expand...
I like your thinking.is there anyone on here who is..a growing journal etc.so i could view
Keeping my options open .its all about heat for me choosing these lights.
 
Tas devil

Tas devil

Well-Known Member
Prices here for fixtures are out of this world.growers choices prices are pretty good.it all comes down to freight to aus .i gotta make my mind up lol and grow some babies..
 
boilingoil

boilingoil

Well-Known Member
Tas devil said:
Hi gents just about to get some fixtures for my first grow..as the title says im tossing up
between the 600/750 de fixture and 4 cmh fixtures.i have been told that i will need to run
an ac between canopy and fixture as my ceiling is only 7ft a liitle less once gav is in there.
Im told the buds will b more dense etc.than the cmh.i want to have an efficient setup and
thinking is it worth running ac as want to keep cost down.i just need some friendly help
and guidance which way to go.im not worried about startup cost .being a newby i want to make it as easy as possible.

Cheers
Click to expand...
Gavita 6-750 with 7' ceilings.
DSCN0822.JPG
Covering a 4'x8' area. So don't let people tell you it's not possible to run them with 7' ceilings.
Finished pics.
DSCN0864.JPG
 
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