T12's

[Eric Warwick]

I recently got some old T12 florescent lights from a friend for an indoor aquaponic system. They said they were using it to sprout seeds indoors and it failed. They are 725  lumens; the light is a GE Bright Stick. Should I use them, and what are some peoples experiences with them? Thank you in advance.

[Edward Pozek]

t12 are some old tech in florescent lighting. I would only use them to light up a room if that. You would be much better off with t8 or better yet, t5. My indoor setup uses t8 and I'm getting very poor growth on anything that fruits. It will grow your lettuce just fine though.

[Eric Warwick]

Yeah, I'm going to buy some T5's (maybe T8's) , any suggestions of where to get them?

[Edward Pozek]

I got my t8's at Home Depot but I have seen some T5 fixtures online for the same prince. About 150 bones will get you 6 bulb fixture, maybe a little more.

 

[TCLynx]

Just make sure you can adjust the height of the lights since Florescent fixtures need to be very close to the plants to be of any real use to them.

[Vlad Jovanovic]

I'm having real good luck sprouting all kinds of stuff with a pair of 38 Watt T8's...And the leafy stuff (lettuce, spinach etc... does well beyond just sprouts)...I have them set up on chains so that height is adjustable. They don't really heat up at all, and the tubes are super cheap to buy. (And probably should be replaced after six months). Not even gonna try anything that flowers and fruits.

[LogicalHydro]

That's great to hear! I sprout and clone with only 1 HO T5 and have always had great results with everything. The HO T5 2' are around 24W and 4' are 54W. The bulbs are a little more expensive than the T8's you use, but they offer a more efficient spectrum. 2- T8's should get your plants fairly big.. atleast well beyond sprouting

[Vlad Jovanovic]

Yeah the T8's seem to be working well (for what I intended them to do, which is just sprout lettuce). Just for giggles I left a pepper plant under them for about a month after sprouting and it looked rather scraggly and etiolated...Those T5's (from just about everything that I read/hear) seem to be the way to go as far as florescent. I ordered four sets of Phillips 400 Watt HPS/MH combos. I could really use the heat over the winter time.

[LogicalHydro]

Yeah, they will work great for sprouting lettuce. Just keep it cool and the light close or they will bolt. IMO T5's are the way to go for extended grows in terms of fluorescents.  

 

That's an excellent way to heat your room. Way to plan ahead of time on that one. It will be sure to save you money since you can use the radiant heat to your benefit. What configuration are you putting the lights in? 1600 watts will be nice heat and an excellent grow. 

[Vlad Jovanovic]

The plan as far as lettuce is concerned is to sprout them in 2” net pots in the garage where I have a 2’ by 8’ area set up with 2 pairs of T8’s. After about a week I plan on moving them into the greenhouse on a dedicated sprouting table 4’ by 8’ with one  400 Watt MH bulbs over half (4’ x 4’) the sprouting table and a set of 4 T8’s on the other half (just for comparisons sake),and baby them there for another week. Then move them to a DWC nursery trough (ala Friendly’s) with 2 sets of 400 Watt MH for another week (3 weeks total thus far). Then move them out to the 512 square feet of final grow-out troughs where there will probably not be any supplemental lighting due to the cash involved and perhaps bolting issues.

 

The site grading and preparation for the 2131 square foot greenhouse was completed today. Inside will be 128 square feet of media beds (mainly acting as just bio-filtration and mineralization through this first winter) which then flow out to 512 square feet of DWC troughs…

Does the lighting sound like a good plan (for a winter regime)? My idea was to sorta give the plants a good start in the first 3 weeks or so of their existence and then let them do their thing…I'm interested in your opinion as I'm sure that you have much more experience and knowledge in all issues pertaining to lighting...

 

[Vlad Jovanovic]

Here's a block diagram of the layout (mostly)...I forgot to mention that the nursery trough is 4' by 10' which might be stretchin it for the 2 MH bulbs?

Vlad Jovanovic said:

The plan as far as lettuce is concerned is to sprout them in 2” net pots in the garage where I have a 2’ by 8’ area set up with 2 pairs of T8’s. After about a week I plan on moving them into the greenhouse on a dedicated sprouting table 4’ by 8’ with one  400 Watt MH bulbs over half (4’ x 4’) the sprouting table and a set of 4 T8’s on the other half (just for comparisons sake),and baby them there for another week. Then move them to a DWC nursery trough (ala Friendly’s) with 2 sets of 400 Watt MH for another week (3 weeks total thus far). Then move them out to the 512 square feet of final grow-out troughs where there will probably not be any supplemental lighting due to the cash involved and perhaps bolting issues.

 

The site grading and preparation for the 2131 square foot greenhouse was completed today. Inside will be 128 square feet of media beds (mainly acting as just bio-filtration and mineralization through this first winter) which then flow out to 512 square feet of DWC troughs…

Does the lighting sound like a good plan (for a winter regime)? My idea was to sorta give the plants a good start in the first 3 weeks or so of their existence and then let them do their thing…I'm interested in your opinion as I'm sure that you have much more experience and knowledge in all issues pertaining to lighting...

 

[LogicalHydro]

Vlad,

 

That sounds like a great setup. I love the layout of the entire greenhouse. I think that giving them a good jump during the first 3 weeks will be an excellent idea. 

 

As far as just sprouting with T8's for the first week, I strongly agree.

 

As far as the second week, I think the comparison will show you what results to expect. Keep the T8's as close to the plants as you can while still allowing them to cover all plants. You can always rotate net pots too if the ones on the edge start to grow sideways to get to the light. MH 400W usually are most effective at a height of 1'-4' above the plants. The closer they are, the more likely they are to burn the plant and the less horizontal area to cover, but the more lumens go to the plants. I have also run a 600W MH around 1 foot above plants and been fine with an air cooled fixture, so your cool winter should help with this. To reach 4'x4' or a 4'x5' area you might have to put them a little higher than you would like, but experience will help with that. The cheapest thing you could do is probably supplement with fluorescents. 

 

And as far as the third week, I think it sounds beneficial as well. It might take some playing around with heights of your lights, but I know you will find a happy medium. 

 

I think your entire setup sounds like a great idea! I can't wait to see how everything works out for you!

[Vlad Jovanovic]

Thanks for the encouragement. I was going to use a 4 foot height as a starting point work from there. Since the lights are 400 Watts, and the grow spaces are all 4 foot wide...

Is there a safe minimum outside air temp that you know of for these MH bulbs and ballasts?  I've search the net, and asked at the hydro shop where I bought the lights, but no solid info?

I cant wait to get started either, it's been one hold up after another...from customs agents to contractors.