t5 vs hps??

i have a 4 foot tf high out put i think 374 or 394 watts something like that and a 400w hps is there gonna be a huge diff flowering with the t5 instead of the hps besides the penetration and lower buds due to same wattage?

thats looking for a war on here .i use a small t5 and 2 4ft t12s i would love to find out which is better myself the hps puts out too much heat it cost more
to buy .and to run lol you will need a vent if not an air conditioner or both all to run a light that gives you a little bit better bud . is all i see with hps but thats my opinion

From what ive read hps is going to give you more lumens per watt and better canopy penetration. From a "put the light above the plant and see what happens" point of view HID wins, but like the previous poster mention youll need extra heat control which could mean ducting etc. All lights of the right spectra can produce good crops if the lumens are there, its all about using the lights output effectively.

hps lights will let the plant produce more of the oils inside the buds i forget what the correct name for it is.search for garden of dreams he is really good at answering that question.he gave me a great explination when i asked the same q

I have a 6 tube T5HO fixture (5 feet type as I got em for free at work)

I have new tubes in it .. 4x 6500K and 2x 2700K .. all 49W with a total of 27,900 Lumens ..

I use em to Veg with





did a great job on my last 2 volitaor kush plants witch I veg under them for about 6 weeks (one is FIM other LST)



day 37 from seed .. a week or so before I begon 12/12 with my 600W HPS ..

and here they are at day one of 12/12




trick with tubes/CLF is to keep em low with a even canorpy (top/FIM and LST) as the only real down side of them lights is penetrations ..

my light meter dont show mouch after 10 inch`s .. after 12" I dont even get a reading ..

I found out my plants do best 2-4 inch`s away .. one is to close ..

at 2 inch I get around 1,5K foot candles = 16K Lumens per sq ft.

from 4 and down to 10 I read around 800-1000 Fc. = 8500 - 10K lumens Per sq ft ..





T5 is superior to boath T8 and T12 (if I had to choose between T8 and T12 I would anyday choose T8 )

boath when it comes to life spand and light lost over time T5 is way better (look for very dark ends at the tubes .. if so they are old and need to be changes .. around evry ½-1 year depending on use)


but if its the normal T5 type (14/28W mostly) they actualy dont give mouch more light output then T8 58W

need to get the HO type (HO = high output) witch normaly comes in 28/56W (28W is 2 feet type 56 is 4 feet .. watt determin lenght of tubes)

or even VHO (very high output) with I belive comes in 80W or sumthing .. dunno dont know mouch about them .. need cooling I belive ..

I can touch mine with out a problem .. temps under them normaly get 1-3 celcius higher then the room they are in ..


I flower under a 600W HPS (2100K) with provide 92K Lumens ..

and my light meter .. even 2 feet away shows +5K foot candles !!! more then 3x the T5HO 2 inchs away .. even pointet at the maylor I get atlest +3K

at 1 feet awaay I get +7K = 75K Lumens per sq ft.




so a HPS on double the watt will provide you with atlest 5x the light output .. roughly .. and mouch better penetrations ..

with that said .. I actualy do consider to down scale at some time in the near future ..

get atlest 4 T5HO tubes more so I have 10 and close to 50K Lumens ..

with out the HPS I can runn a lot less ventilation and keep it small ..

tho even with evry thing spot on and maybe even in hydro ..

I will expect atlest 20-30% less yild per plant then with a HPS .. and I even have to work for that .. a lot of traning to keep buds right under the tubes .. so I dont get to many pop corn buds out of it .. but if it do cover my need .. I will be happy to cut the high heat .. high power use .. also safety is a topic with a HPS aso.

hope this give you a better pictur .. ask if you got any specific questions about T5 or anything ..

Hi Slipon,


Nice post!! lots of useful information. My question is this: I was considering 4ft T5HO 8 bulb at about 450watts and 38,000 lumens. But I am intrigued by the increase in efficiency of HPS. More lummens to watt ratio. I will be growing in a 4ft x 2.5ft closet with a 4"vortex to pull fresh air thru. My one concern is the heat. I am guessing heat is the primary safety concern? I am thinking of going with 250watt hps now for flowering at 32,000 lumens. It seems because of the penetration issue, that 32,000 lumens of HPS would still be better than 38,000 lumens of T5HO. I am really concerned with heat and fire, because I know the seriousness of that stuff. My parents house burned down when I was younger, I was there and had to help my mom get out in just the nick of time!!! (faulty BBQ gas grill too close to house). So i am ultra careful and cautious. some hoods have vents in them, maybe that is a safe option.

thanks

and yea your right .. they do produce a lot of heat so do be carefull (as a minimum make sure to place a good fire allarm close by.. I do)

tho dont worry to mouch .. they aint made to chatch fire .. use commen sens and logic .. dont build the box out of cardbord Etc.


I run mine at night for a few diffrent reasons ..

for one .. tempertures is lower and that is a great advanges .. power might be cheaper witch I dont mind ..
and Im home from lights on and untill I leave for work in the morning on week days ..

that way Im mostly home when the light is on .. boath to keep a eye on the lamp but also so I can work on my plants aso.
works for me .. tho the fire allarm just out side my grow room do make me sleep with peace in my mind


and yes cool tubes/hoods is a good option and one I would choose anyday if I could do it over ..

actualy I just did .. just build a cool hood at work ...




did`t try it out yet ..

is a bit concernd with the glass and alu tabe .. if it can handle the heat ?
but I still need to add some 4" alu tubeings and my 4" vent (also run a 6" vent with a carbon filter on to clean smell and keep overall temps down in the room )

and Im also still in Veg. so my small babies is still under my T5HO fixture ..




but yea a cooltube in a small place is kind a must I would say .. will keep temps down and that will boath help your grow and safety ..

so if it was me .. with your space ..

I would either go for the best T5HO fixtur I could get in ther with the right bulbs .. new in the right kelvin ..
and grow 4 small kush plants or Autos under it .. keep em low and even and close to the T5HO and expect to yield the same as 2 plants under a HPS .. but with less power used and less heat/safety isues and less need for big ventilation system and ACs (also less power used) a small 4" is about right ..

or get a 250W MH/HPS ballast/bulbs and cool tube and grow 2 plants under it .. they will yield atlest the same I reccon and maybe with denser buds .. but with more power used aso.

also need to consider if your life in a place wher they use choppers to watch for heat/grow rooms ? I dunno if your leagel .. but atlest consider it ..

a 3Th option would be to get a nice 400W MH/HPS with a digital ballast and a cooltube/hood and a good 6" vent and grow 4 plants under it ..
would be kind a perfect for your space I belive .. but I dunno about your hight in the room .. and your tempetures in your part of the world ?

ther is actualy a 4th option (and I bet many more .. but of what I can think of)
LED .. they are expensiv and you need the good more expensiv once if you want one that works proberbly ..
but they use way less power and close to no heat .. so safety is in top and power use is so low that it will pay for its self over time compaird to a HPS .. also since they last longer but to start with you need to come up with +500$ I would say .. but also less on ventilations aso.

they will grow dens buds .. close to a HPS with the power/heat close to T5 .. so best from boath worlds ..


hope this can help you make the right choise .. keep asking questions and do some research/googleing ..

Ooh yea and a link to my other thread with similar topic:

https://www.rollitup.org/general-marijuana-growing/542459-light-distance-reflection.html

T5s are meant for early veg, nothing else. I use T5s from germinated seed in soil to about week 2-3.

sure ...