View Full Version : Help with lighting

08-16-2009, 09:18 PM
Hello and thanks for reading. I have read a lot about the lighting systems available on the forums. I have researched the different lights through Youtube and find very little info on T-5 vs. MH and/or HPS, that looks like someone did a study or a realistic comparison. Since I am on a limited budget I have several questions, and will be starting with T-5's.

New Wave T-5 2' by 4 bulb(24w each). I plan on having 4x6500k and 3x 3000k spectrum lights available for the different phases(veg and bloom).

1. The output should be 20,000 lumens and I would line my grow area with Mylar(2'x3' x 4.5'h). Would hotspots be an issue(how and/or why not)?

2. In an area that is so cramped, would hanging the light vertically in the center against the back be a bad idea? Compared to a horizontal mount, several inches above the top of the highest plant?

3. I will eventually change to MH and HPS, but I find no info on what exactly and A/C fitting on those bulbs is/ how it works. I also realize that the grow area would have to increase significantly to use MH and HPS.

Thank you for reading and posting :)

08-21-2009, 10:44 PM
hhmmm were to start :P.

ok so you want to grow from start to finish with fluorescent lights?.. t-5, T-8,T-12 are all the same, just difference in tube size.

right now i use 6 t-5 grow strip lights for my veg room, 3 on the top and 3 on the bottom, mothers on top seedlings and clones on the bottom...

... to get significant results you would need 8 or more fluorescence to get enough to produce good fruits..

now regular plants wouldnt need this mucht light but im giving you an example. i would consider buying the HPS lighting for your flowering then using fluorescence.

cost?, $180 for 6 fluorescence, $275 for a 400W electronic HPS ballast plus 30$ for the 400W lamp. you would generate heat this way but all you would need to do is buy a 4" fan.

LUMENS dont matter for plants, lumens are there to calculate how much the human eye sees, its the spectrum that matters!!! dont get me wrong the plant needs full spectrum lighting through out its life cycle but uses more of red or blue during the vegetative or flowering phase.


using a lot of fluorescence will give you results, but none seen with using HPS or MH..

some people use HPS throughout the whole cycle though. i've just read a mini article on how MH is better during the last few weeks of flowering because of the unique colour spectrum it puts out.

its all up to you(the grower) to decide what your going to spend all the hard work using though.

08-23-2009, 07:13 PM
Thank you DJ for answering, it's something that I will be running some experiments with in very controlled enviroments/nutrients, with mixed lighting through the different phases. I'm still a bit confused whether or not mh/hps would be better for flowering, so I am gonna run some great tests with pictures over the next year.

Thanks again -Ryan

08-24-2009, 07:27 AM
as a newbie to this hobby I was also a bit confused on mh/hps vs flourescent lights. the bottom line thought when comparing hid's vs floro's is lumens. and hid's put out alot more lumens in comparison. this is important because while either floro or hid will veg a plant as the plant grows and gets fuller and bushier floros dont penetrates the canopy as well as hids. so what that means is hid's will get the light where you need it where floros are only good for the top layers. Plus i've read where the yield is 3-4 times as much with hids than floros. also to note during the veg cycle mh are used and during flower hps are used. they say that a 400 hid light will cover a 3x3 grow area, 600 for 4x4, 1000 for 8x8.
my area is 5feet wide by 5 feet high by 2.5 feet deep. so i plan on getting a 400watt hid set air cooled and on a light mover to sweep left to right for a nice even canopy. right now i am using a 125 watt compact florescent with a bat wing reflector for cfl bulbs. but right now cant really report how well its doing since i have nothing to veg yet. (I hate germinating seeds)

Heat is another concern with using Hid's if you get an air cooled reflector or a cool tube then you can vent the air with a blower. but to maximise this benefit is to draw in air from outside the grow area and exhaust it out of the grow area. by doing it this way you get 2 benefits 1 less heat in the grow area to manage, 2 you can have the light lower to the canopy without damage to the plants.

I am continuing to research the cost of these hid lights but for what i can see the newer digital ballasts will light both mh and hps. and you can get quite a few nice deals on ebay. for under 200 ballast bulb reflector.compared to magnetic ballasts digitals are superior, mind you though with some magnetic ballasts they have a switch to change from mh to hps. not all magnetic ballasts have this switch so you need to be careful if your planning on vegging and flowering with the same ballast. plus on the negative I have heard that magnetic ballasts are more noisey with humming and such where digital ballasts are silent. so if you plan on do it in a stealth manner digital is the way to run.

also as for hotspots when your working with floros thats not a concern

David G.
08-24-2009, 01:33 PM
A 1000W light will NOT cover an 8x8' area, unless you are growing house plants that have very low light requirements. If you are growing plants that prefer full sun, a 1000W will cover no more than a 5x7' area. We have many customers who actually run 1000W lights over areas as small as 4x4' with excellent results in terms of growth rates and yields.

DO NOT purchase a no-name digital ballast from eBay, or anywhere else for that matter. I say this not because I work for BGH and I'm trying to persuade you to buy from us - I would rather see you buy a quality digital ballast from one of our competitors then see you waste your money on an inferior ballast from eBay.

When it comes to digital ballasts, the saying "you get what you pay for" is 100% correct. We have tested dozens of off-brand digital ballasts and found that ALL of them had problems, the two most common being extremely high failure rates, and horrible lamp compatibility issues.

These ballasts usually come with short warranties, normally 2-3 years or less. You may find off-brand digital ballasts with warranties lasting as long as 5 years; this is possible due to the fact that these Chinese ballasts cost the retailer as little as $50 or less, so they can afford to deal with the high failure rate. But it will still cost you money to ship it back and forth each time it fails (and it will fail, just give it enough time), not to mention what will happen to your plants while you wait for the replacement to arrive.

These ballasts also are frequently sold as a complete kit, with the reflector and lamp included. The reason for this is that they know the cheap lamp they include with the kit will work with the ballast. 6 months later when it's time to replace the lamp and you choose a high performance grow lamp (Hortilux, Solar Max, etc.), the trouble begins. Most of these ballasts are not compatible with high performance lamps. Also, the reflector and lamp they are selling you are usually pieces of junk. The lamp has a low PAR light output, normally manufactured to Chinese specs instead of North American or European specs, and the reflector doesn't reflect nearly as much light as a properly designed reflector using highly reflective German material.

$200 might seem a lot cheaper than what respectable retail shops are charging for systems using ballasts like Lumatek, high-end air-cooled reflectors that were properly engineered and tested (like Sun System), and lamps that produce the proper amount of plant-usable light (not just light that appears to be bright to the human eye). But in my opinion, you would just be throwing your $200 in the trash.

Sorry if I sound like I'm going off on a rant (well, I guess I am actually...). I just can't tell you how many sad and angry customers we have had to deal with who made the mistake of purchasing one of these ballasts, and then got stuck with a $200 paperweight when the company they bought it from wouldn't stand behind the product. Seriously, I am taking the time to write this in hopes that I can prevent even just one person from making a costly mistake; if I can prevent even just one person from making this mistake, I will feel totally justified in having spent the time to write this. And whatever decision you ultimately end up making, I wish you good luck!

08-24-2009, 02:47 PM
T-5, T-8, and T-12 are not all the same. With T-5 you can get HO fluorescent lights wich have a 5k luman output per bulb. With T8, and T12 you CAN NOT get this type of output. Also T-5 bulbs are not compatiable with T-8 or T-12 fixtures nore are T8 or T-12 bulbs compatiable with T-5 fixtures.
T-5 - High Output bulbs give 5k lumans
The 54w ones give 5k lumans (4 foot blulbs)
The 24w ones give 2k lumans (2 foot bulbs)
T-8 - Max output I can find are 3.1 k lumans
T-12 - older model bulbs not worth using (other than seeds/sprouts)

1. So a T-5 using HO bulbs 2' using 24w bulbs with 4 bulbs on it will only give you 8k lumans. For the same price you can get a 4 foot 2 bulb T-5 HO system which insted your grow bed will have to be loner and narrower but you'll get 10k lumans thats a 25% increase in lumans over the same surface area. I know the 2 foot ones are cheaper but the 4 foot bulbs give 25% more luman per square foot than the 2 foot. Trust me you'll kick yourself in the end if you go with 2 foot bulbs.

As for DJ lumans don't matter if they arn't the right spectrum however...with the new HO bulbs it would be easily arguable that T-5 florescent bulbs are as good as MH. MH has higher output but the T-5 u can keep a lot closer gaining back your light. As for HPS they are better...but my T-5's will last forever where as the HPS won't and you have to worry about heat as well.

Personally it comes down to a lot of things like budget, space to work with and most importantly the plants your working with. I work with smaller plants like lettuce, herbs, and other tube plants that are usually 15 inches or shorter with great sucess...however...it is possible you could have canopy penetration issues if you were growing tomatos or taller plants with fluorescent blubs (from what I have heard not expereinced).

08-30-2009, 08:04 AM
Everybody stocks 4' fluorescent lamps, T12, T8 and T5.

18", 24" and 36" fluorescents are rarely stocked.

David G.
08-31-2009, 03:51 PM
BGH stocks T5's in 2' and 4', both blue and red spectrums. We also stock 2' and 4' T12's (Verilux, much better than standard cool white's for growing plants).