T8 Lights Height and Height of Plants

Trippyness

Trippyness

Well-Known Member
Hello all.

So my plants are doing well at 2" and they are 3 weeks old now from seed.

They are about a middle finger long and am wondering if they will get larger and larger or should I move the T8 bulbs up some? Just want to get a answer on this as it seems they are taking quite some time to start serious growth.
I have good ventilation and good lighting.


How tall should they be at this point?
Strains are
Cotton Candy
Purple Haze

Experience needed not just assumptions.


 
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churchhaze

Well-Known Member
Earlier today you were lecturing another noob about how to use t-5 and t-8 and "the correct veg spectrum", but now you want "experienced replies only" and not assumptions... on how far to keep your light away from your seedlings...

Why should you get experienced advice, but the person you helped got noob advice?

https://www.rollitup.org/t/starting-seeds-under-200-w-led-with-both-vegging-and-flower-switch-on-ok.865987/

White LED is best on VEG setting. Please do some research on spectrums.
Second, I would suggest you get some T5/T8 bulbs as they are very good for seedlings and Veg.
White LED need to be within 2" of plant to prevent stretching. I heat is an issue use a fan but with LED its unlikely.
Move the LED up once plants get larger. 12-18" for larger plants but again the closer you can get the light the better penetration you get and the larger production.
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Then you come here and basically ask how far you should keep your t8... experienced members only.... sure..... How about a deal.. I'll tell you how far you should keep your t8 from your seedlings if you stop giving other noobs lectures on how far they should keep their seedlings from their lights.

You even argued with a more experienced member who has experience with MH for seedlings.

In what way do you disagree? Regardless of indoor or outdoor he needs a dedicated Veg Room and light.
Sure MH can be used but its very difficult to get them very very close without stretching withing heavy ventalation.
A simple T8 fixture will do perfect.
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It sounds like you already have a lot of experience with T8.. this thread should not exist. You're basically asking us how to count while simultaneously trying to teach a math class.
 
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Trippyness

Trippyness

Well-Known Member
churchhaze said:
Earlier today you were lecturing another noob about how to use t-5 and t-8 and "the correct veg spectrum", but now you want "experienced replies only" and not assumptions... on how far to keep your light away from your seedlings...

Why should you get experienced advice, but the person you helped got noob advice?

https://www.rollitup.org/t/starting-seeds-under-200-w-led-with-both-vegging-and-flower-switch-on-ok.865987/



Then you come here and basically ask how far you should keep your t8... experienced members only.... sure..... How about a deal.. I'll tell you how far you should keep your t8 from your seedlings if you stop giving other noobs lectures on how far they should keep their seedlings from their lights.

You even argued with a more experienced member who has experience with MH for seedlings.



It sounds like you already have a lot of experience with T8.. this thread should not exist. You're basically asking us how to count while simultaneously trying to teach a math class.
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I may have worded this wrong.
First of all I am not a pro. Second MH is a bad idea for seeds due to heat.

Your correct this post is useless as I just wanted aan answer as to how high can the lights be put without loss of light penatration. 2-4 inches. My apologies deleted
 
Sativied

Sativied

Well-Known Member
Trippyness said:
So my plants are doing well at 2" and they are 3 weeks old now from seed.

They are about a middle finger long and am wondering if they will get larger and larger or should I move the T8 bulbs up some? Just want to get a answer on this as it seems they are taking quite some time to start serious growth.
Click to expand...
As you concluded already in that last sentence, they aren't actually doing well for 3weeks old. I have seedlings under T8 right now which are at asimilar stage but barely a week old. At 3 weeks they will no longer be seedlings but have 4-6 nodes. You ask if you should move the bulb up, while I can't even see it in the picture. Meaning you should probably move it down. There's roughly an inch space between my 3x18w T8 and the plants.
 
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churchhaze

Well-Known Member
Trippyness said:
Get a Hortilux 400 MH and 8 T5. Youll see the differance in heat. I use T8 instead of T5 for the heat reason.
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Just because something operates at a lower temperature does not mean it generates less total heat. Heat is very different from temperature.

You can easily have a 100W heat source operating at 25C while a 1W heat source can easily have a temperature of 100C. Temperature doesn't' tell you how much heat is being produced. A t-8 being cooler than a t-5 does not mean t-8 generates less heat per watt of electricity dissipated. A MH bulb having a high temperature does not tell you it generates more heat than a long tube with a lower temperature.
 
CCCmints

CCCmints

Well-Known Member
your plants are not doing well...you can tell they need a closer light by the long stretchy stems. i used an 8-bulb t5 for veg and these are what my plants looked like at 3 weeks from seed...i'd honestly start over if i were you.

 
R

Rentaldog

Well-Known Member
CCCmints said:
your plants are not doing well...you can tell they need a closer light by the long stretchy stems. i used an 8-bulb t5 for veg and these are what my plants looked like at 3 weeks from seed...i'd honestly start over if i were you.

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Probably save some time by just replanting and burying the plants deeper so only the foliage is above the soil. Something along the lines of "Replant those stretchy stems" :P
 
tokingtiger

tokingtiger

Well-Known Member
I started with t8 and spiral bulbs in splitters. 4x26w on top with the shop lights on the sides. Then I started to get the 3w LED's for top. just replaced the last shop light with a new 200w (actual draw) LED that has 5w diodes. my older 3w diode lights for side lighting. I have cut my electric bill and heat signature greatly, (from cfl's). While increasing the size of my fruit.

#1 rule for CFL is you need to keep them right up in the plants face. adjust daily to not burn close or get bad grows as a result. CFL will work, especially kept small but nobody I have ever talked to that moved away from CFL said they would go back to CFL for the awesome results.
 
Sativied

Sativied

Well-Known Member
tokingtiger said:
keep them right up in the plants face. adjust daily to not burn
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Exactly. Though initially obviously every other day or so will suffice.
1.jpg

This was my second indoor grow, 8 years ago. I still use the same closet + fixtures, obviously replaced the tubes a 'few' times. I use this setup to pre-veg, meaning from germination to about 4 nodes before I move them to MH/HPS closet. In this pic however I vegged way too long, these are about 6 weeks old. The fixtures are fixed at the ceiling, I lower the plants instead of raising the light, sometimes some plants a little more than others so they are all as close as possible.
2ndgrow.jpg
 
Trippyness

Trippyness

Well-Known Member
Sativied said:
Exactly. Though initially obviously every other day or so will suffice.
View attachment 3386909

This was my second indoor grow, 8 years ago. I still use the same closet + fixtures, obviously replaced the tubes a 'few' times. I use this setup to pre-veg, meaning from germination to about 4 nodes before I move them to MH/HPS closet. In this pic however I vegged way too long, these are about 6 weeks old. The fixtures are fixed at the ceiling, I lower the plants instead of raising the light, sometimes some plants a little more than others so they are all as close as possible.
View attachment 3386910
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This is how long from seed?
Seems my plants are doing fine now growing well.
This is 6 weeks from seed or 6 weeks from actuial veg?
 
Sativied

Sativied

Well-Known Member
Trippyness said:
This is 6 weeks from seed or 6 weeks from actual veg?
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Those were 42 days after the seeds popped or after I placed them, don't remember.

Sativied said:
I have seedlings under T8 right now which are at a similar stage but barely a week old. At 3 weeks they will no longer be seedlings but have 4-6 nodes
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4-5 days later now and they are similar to the ones in the first pic in my post above.
 
Trippyness

Trippyness

Well-Known Member
Sativied said:
Those were 42 days after the seeds popped or after I placed them, don't remember.

4-5 days later now and they are similar to the ones in the first pic in my post above.
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When did you put them under MH?
Also how close did you have your MH light to them?
Just wanna get soem more info from experianced growers.
Read alot and am growing
 
vostok

vostok

Well-Known Member
I'm old school and use T8's from post germ to 3rd-4th lateral, my T8's are 4ft long and on a bank with 6 other tubes with a pc fan in the center horizontally to extract any heat ..and just to keep the air moving, I'm choking 3350 lumen each tube and burning 30 watts an hour, but budget 40w ph, as these are old as fuck now, best is I've counterbalanced the whole rack on 2 x8Kg weights at each end, filling some old whisky bottle tubes, with cement ..lol I've been using this system since the early 1980s, even tho I have a shit load of other options I always fall back to this old junky system ,,it cheap fun and highly efficient, after 2-3 weeks in this they are moved to the ASbESTOSpacked 400w Mh, then usually outside to the sun, or to the 600w hps, but I prefer the sun, as much as possible, many many tricks to pick up ...like stripping all the laterals off the lower sections, if you wish to bub under these T8's as the light don't go far, and inprovves air way too,

Always have 75% of your tubes at 2700k and the rest cool whites at 6500k

peace
"V"
 
Sativied

Sativied

Well-Known Member
Trippyness said:
When did you put them under MH?
Also how close did you have your MH light to them?
Just wanna get soem more info from experianced growers.
Read alot and am growing
Click to expand...
Those were a very old example and I flowered under 400w hps back then, no MH.

Nowadays that's roughly 2 weeks after germinating. I usually call those first two weeks preveg, and top them too a couple of days after moving them to mh closet. There I use the 400w mh for 1-3 weeks (1 for hydro, more for soil) and then somewhere during transition I switch to 600w hps.
 
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