Useful lifespan of 2x overdriven t8? - The Planted Tank Forum
 
LinkBack Thread Tools Display Modes
post #1 of 5 (permalink) Old 11-29-2003, 11:10 PM Thread Starter
Algae Grower
 
Join Date: Nov 2003
Posts: 28
i don't have any experience with overdriving bulbs but was wondering if there is a consensus on it's effect on useful bulb lifespan (i.e. decent maintenance of it's initial spectral distribution and light output) when done on the order of 2x overdriven. as i understand it t8's, with proper cooling, have a useful between 10-14 months at which point the decline rapidly. is that number fairly accurate and what would it be at 2x overdriven with proper cooling? i never saw a clear cut answer in the threads i have read but i may have missed it so feel free to post a link if it has already been discussed ad nauseum. thanks.
05dr is offline  
Sponsored Links
Advertisement
 
post #2 of 5 (permalink) Old 11-29-2003, 11:37 PM
Planted Tank VIP
 
GulfCoastAquarian's Avatar
 
Join Date: Jul 2002
Location: Winston-Salem, NC
Posts: 3,578
The 10-14 month lifespan generally applies in relation to color spectral shift, not output intensity. A bulb will produce a fairly high initial lux intensity (say, 4800 lumens, for a GE 9325K 55 watt PC bulb) and then quickly drop off to near its average luminosity (4080 lumens, for the same bulb) after only a hundred hours of use or so. The bulb will stay near its average luminosity for its lifespan (generally 10,000 hours over 2 years with a 12 hour photoperiod.)

All that being said, there is no official study of how long ODNO bulbs last. I've noticed some blackening of the bulb ends after about a year of use, at whic time a fresh bulb will show considerably improved output.

- Sam P -
plantedtanker in limbo - all tanks currently in storage
GulfCoastAquarian is offline  
post #3 of 5 (permalink) Old 11-30-2003, 03:05 AM Thread Starter
Algae Grower
 
Join Date: Nov 2003
Posts: 28
guess i got confused. is it with metal halide that they maintain the same output but consume more and more power to do so?

what is your opinion on how long the spectral shift remains normal with t8's? is the 10- 14 month rule accurate or is there a more specific answer based on hours (excluding actinic or 50:50 bulbs which i heard age faster due to instability of actinic phosphors)?

what is your guesstimate as to how long one can overdrive (x2) a bulb (hours or months, whatever works) with reasonable maintenance of it's spectral output and lumen output? i presume less than 12 months based on the difference you noted when you changed the bulbs.
05dr is offline  
post #4 of 5 (permalink) Old 11-30-2003, 10:52 AM
Planted Tank VIP
 
Join Date: Oct 2002
Location: Lebanon, CT
Posts: 4,939
I use these bulbs and still have good growth after a year... one is Overdriven 2x and the other is overdriven 3x... ZooMed Lighting

I like the UltraSun (6500k) and FloraSun (8500k) bulbs.
Buck is offline  
post #5 of 5 (permalink) Old 12-01-2003, 01:52 PM
Planted Tank VIP
 
GulfCoastAquarian's Avatar
 
Join Date: Jul 2002
Location: Winston-Salem, NC
Posts: 3,578
Plants aren't as worried about the spectrum shift, so I wouldn't replace a bulb in a planted tank for that reason alone. Diminished luminosity won't occur for at least a year so I've been replacing bulbs at the 12 month mark. And that's only because these are cheap $4 bulbs.

- Sam P -
plantedtanker in limbo - all tanks currently in storage
GulfCoastAquarian is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Confused about materials for overdriven lights hubbahubbahehe Lighting 6 03-16-2004 07:42 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome