What light for me?

[Brad]

Hey guys, I am in the middle of building a new grow room the dimensions are H:1300mm W:750mm D:500mm and im going to buy a new light either a 400HPS or a 600HPS im leaning towards the 400 because of the heat factor my fan clears 64L per second so its quite a large fan. When i put these dimensins into the OS calculater it came out that i could only have a maximum of 250watt.....? your opinions would be very helpfull.

[Dave The Nefarious]

Given those dimensions I would've suggested a 400w (ive just got one 600w in a 2m x 2m x 2m space and in summer that gets warm enough for my liking), but then I don't know how much cooler 400 watters run compared to 600 -- anyone ????

 

Another trick to dealing with heat is to have your lights-off period during the hottest part of the day, so your plants daytime will be our nighttime and vice versa

[Stoney]

hey there

 

the best would be a 400w for those dementions but if you wanted to include a cool tube then you could go the 600w the 600w would give ya heaps better light coverage but as i said a cool tube would be needed

 

cheerz :Dj:

[Shithappens]

Your choice man a 400 to start with would be my advice

 

but with a 600 and the probable need to increase your fans could be done since you are still in construction.

 

Once you have plants in there it will be a fair bit harder to alter, especially if you go the 600 and summer hits as hard as they say it is going to.

 

Play it safe less yield is better then fried cuttings in a few months.

[Samjana]

hi

 

my room was 800x900, 1600 high running a 400w, I used a 150mm standard bathroom extractor fan (inline) and a small fan inside. My temps got as high as 40 deg C, this was my first grow, middle of summer - on @ night, in attic. So heat was a mojor issue. Good grow for first.

 

hope that helped. My advice go straight to a decent centrifugal extraction fan - one of my best buys - light being the best

[thc24]

400wt= from 75cm x 75xm upto 1m x 1m

 

 

600wt= 1m2 upto 1.5m2

 

 

1000wt= 1.5m2 to 2m2

 

 

if you chose to go the 400 your going to need more airflow than someone in a grow tent 1m2, to control temps in summer. the price you pay for a 400wt isnt that good when compared to the 600wt so the 600 is abetter choice but wouldnt suit your room maby think about scrapiping the cupboard and go for a purpose built grow room from alli tube perfectly suited to a 600wt. 50% more yield for an extra $30 to $50

 

I know someone growing with a 400wt in basicly same size room as yours, has a couple of cpu fans sucking fresh air in, one 300mm bathroom fan to exhaust 24/7.

 

In summer his temps are above 30c but only for 2 months in peak of summer, an oscilating fan is a must in a small grow this will help to even out the room temp, your room will have differing temps eg 23c on the floor, 25c canopy level and upwards of 30c at light height and above, oscilating fan evens out the temps so there is omly slight differance from top to bottom.

[Brad]

Thankyou all, for the replys!

Thats a big help i think im going to go the 400 as i really dont wanna get half way through summer and my plants a frying. Thanks again

[two2time]

thats a good idea mate , i fryed one today dam it..

 

 

tt