The Planted Tank Forum - Reply to Topic
Planted Tank Forums
Your Tanks Image Hosting *Tank Tracker * Plant Profiles Fish Profiles Planted Tank Guide Photo Gallery Articles

Go Back   The Planted Tank Forum > Specific Aspects of a Planted Tank > Lighting > Lighting an Aquarium with PAR instead of Watts

Thread: Lighting an Aquarium with PAR instead of Watts Reply to Thread
Title:
  
Message:
Post Icons
You may choose an icon for your message from the following list:
 

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:

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.



Additional Options
Miscellaneous Options

Topic Review (Newest First)
Yesterday 04:07 PM
jeffkrol I'm confused why youare wondering about the PAR of 2 bulbs.. You have 6.
Yesterday 08:21 AM
Filet-O-Fish Hi Everyone.
This is my first post here.
I have read from the first page till here and all my previous ideas of lighting for a planted had been blown away. I have always thought the WPG was the right way but now I realize that its not any more.

So I have this problem for my planted tank's lighting.

I have just purchased a T5HO light set.
It can hold 6 pieces of 48" T5HO at 54 watts each. I have also bought six Odyssea brand tubes.
4 pcs - 6400K
1 pc - 10000K
1 pc - red plants ( no K reading on tube)

The light set has individual mirror like reflectors for each T5.
The light set comes with 3 light settings:

a. 2 T5s can be switched ON
b. 4 T5S can be switched ON
c. All 6 T5s can be switch ON.

My tank is (H)48" by (W)18" by (H)22"
Volume: 80 gallons
Co2: Injected Co2
Fertilizers: EI dosing

The light set is now on a adjustable hanging stand.
The light is 8" from the top of the tank and 25" from the substrate level.

According to the graph posted by Hoppy, the Odyssea 2 bulb T5HO 36" is only 35 PAR.
Will the PAR be same for my light set at 25 inches from the substrate?

I intend to go for mid to high light tank.

I'm confused on the exact height I should have my light set and would appreciate the tips or advice given.
Thank you very much.



03-24-2015 04:57 PM
jeffkrol
Quote:
Originally Posted by mattinmd View Post

AFAIK, all the numbers that Finnex has published for final products to date have been Apogee numbers. I think it is only the one pre-production Planted+ that got the University involved, because of the 660nm issue.

I could be wrong of course, but that is my general impression.
That is my assumption as well..
03-24-2015 04:55 PM
mattinmd
Quote:
Originally Posted by jeffkrol View Post
LiCor is university standard for PAR.. I'm sure Finnex didn't want a spectroanalysis
http://www.jstor.org/discover/10.230...=4&uid=3739256
Fair enough... didn't realize universities were using that as a standard.

Quote:
Originally Posted by jeffkrol View Post
Point is "we" don't even know which ones were or were not tested by the Uni..and which were tested by Finnex w/ "their" Apogee
AFAIK, all the numbers that Finnex has published for final products to date have been Apogee numbers. I think it is only the one pre-production Planted+ that got the University involved, because of the 660nm issue.

I could be wrong of course, but that is my general impression.
03-24-2015 04:46 PM
jeffkrol
Quote:
Originally Posted by mattinmd View Post
Technically, it was a university agricultural department, not a contractor.

http://www.plantedtank.net/forums/sh...57&postcount=4

Being a university lab, I would also suspect they used substantially more advanced equipment than a cheap little LiCor... University labs usually have access to equipment well beyond the $2000 price range, at least if they're at all well funded.

Universities also usually have rules prohibiting staff from helping commercial businesses "on the side", as it eats into sources for research grant money. This is probably why that ended. Of course the university would love to help Finnex if they provided a few hundred thou for a research grant. All in the name of advancing science, of course..
LiCor is university standard for PAR.. I'm sure Finnex didn't want a spectroanalysis
http://www.jstor.org/discover/10.230...=4&uid=3739256

Point is "we" don't even know which ones were or were not tested by the Uni..and which were tested by Finnex w/ "their" Apogee
03-24-2015 04:39 PM
mattinmd
Quote:
Originally Posted by jeffkrol View Post
Your memory and mine contradict a bit:
Technically, it was a university agricultural department, not a contractor.

http://www.plantedtank.net/forums/sh...57&postcount=4

Being a university lab, I would also suspect they used substantially more advanced equipment than a cheap little LiCor... University labs usually have access to equipment well beyond the $2000 price range, at least if they're at all well funded.

Universities also usually have rules prohibiting staff from helping commercial businesses "on the side", as it eats into sources for research grant money. This is probably why that ended. Of course the university would love to help Finnex if they provided a few hundred thou for a research grant. All in the name of advancing science, of course..
03-24-2015 12:22 PM
jeffkrol
Quote:
Originally Posted by Hoppy View Post
I think Finnex used a contractor to test their lights, and he used the LiCor PAR meter. That contractor no longer does this for them, so they haven't tested the Planted Plus and published a nice set of charts for them. (I'm relying on my memory for this.)
Your memory and mine contradict a bit:
Quote:
Finnex uses Apogees on their other models. The only data they've published for the Planted + was measured for them by a University research lab, not their Apogee. It was also performed on a pre-production sample of the 24" model, so those numbers are also of limited value. They've got access to a LiCor now, so any future numbers should be reasonably accurate
http://www.plantedtank.net/forums/sh...nex+par+apogee

Quote:
Sorry guys we've been trying to find a new source to get real PAR numbers. We lost our contact in the agriculture dept at one of our local community colleges that had the equipment to get precise data. We do have an apogee but the numbers on the planted+ will certainly be higher than the readings it provides, especially now with the 660nm true red leds.
03-24-2015 04:53 AM
Hoppy
Quote:
Originally Posted by jeffkrol View Post
If you had 35% 660nm red @50% it would be 35x.5 = 17.5% low..



apogee is fine and since it is common in the real world.. you will be able to at least compare to others (Finnex is all Apogee measurements).

Just keep in mind it will be a bit low..
Certainly beats a Lux meter or an "eyeball"..
I think Finnex used a contractor to test their lights, and he used the LiCor PAR meter. That contractor no longer does this for them, so they haven't tested the Planted Plus and published a nice set of charts for them. (I'm relying on my memory for this.)
03-24-2015 02:49 AM
mba Sweet thanks!!
03-24-2015 01:34 AM
jeffkrol
Quote:
Originally Posted by mba View Post
So in simplicity term, worst case scenario would be 10-15% off if you have 35% red (no, only 10-15% red in my set-up) and 66% high K white (No again, mine is a two channels one is 40% warm, 30% 7000k, and the rest is with cyan red, blue).

So I guess my apogee is good to go
If you had 35% 660nm red @50% it would be 35x.5 = 17.5% low..



apogee is fine and since it is common in the real world.. you will be able to at least compare to others (Finnex is all Apogee measurements).

Just keep in mind it will be a bit low..
Certainly beats a Lux meter or an "eyeball"..
03-24-2015 01:25 AM
mba
Quote:
Originally Posted by jeffkrol View Post
Well for a start, if the reefbreeders use any 660nm reds you will only measure, roughly 1/2 the PAR that it emits (depending on diode characteristics).. The Apogee has a sharp red measurement cutoff before "visible red" ends.
In deeper tanks, since some is "lost" anyways" this is not as important as in shallower tanks.
somewhat also applies to low K whites 3500K or less.

you will also under sample blue wavelengths starting at 475nm and less (royal blue on down).

Lastly you will slightly over sample blue/greens to yellow/reds (orange) though this is minor.

Over all the error will not be critical.. but it would w/ measuring a light w/ 35% 660nm red and 66% high K white (6500K or better)

My "big dig" is I'm pretty sure apogee can "do better" if not to Li-Cor quality.. close to..
They use a cheap IR "cut" filter AFAICT which cuts too soon.
Apogee's inaccuracies are well noted w/ LED's and other "broken spectrum" lighting..they jut get a tad more crucial w/ LED.

you may only have, say, a 10-15% under-sample..

I would be the first to admit I'm a bit anal on this point.
So in simplicity term, worst case scenario would be 10-15% off if you have 35% red (no, only 10-15% red in my set-up) and 66% high K white (No again, mine is a two channels one is 40% warm, 30% 7000k, and the rest is with cyan red, blue).

So I guess my apogee is good to go
03-23-2015 09:47 PM
jeffkrol
Quote:
Originally Posted by mba View Post
Jeff,

Can you clarify what issue of the Apogee sensor you are referring to? A newbie like me does not understand the chart you provided with the closed caption. I'm planning to use the new Apogee sensor to measure my LED custom photon 48 planted version from reefbreeders (I believe you helped me build that led light fixture last year and some other users).
Well for a start, if the reefbreeders use any 660nm reds you will only measure, roughly 1/2 the PAR that it emits (depending on diode characteristics).. The Apogee has a sharp red measurement cutoff before "visible red" ends.
In deeper tanks, since some is "lost" anyways" this is not as important as in shallower tanks.
somewhat also applies to low K whites 3500K or less.

you will also under sample blue wavelengths starting at 475nm and less (royal blue on down).

Lastly you will slightly over sample blue/greens to yellow/reds (orange) though this is minor.

Over all the error will not be critical.. but it would w/ measuring a light w/ 35% 660nm red and 66% high K white (6500K or better)

My "big dig" is I'm pretty sure apogee can "do better" if not to Li-Cor quality.. close to..
They use a cheap IR "cut" filter AFAICT which cuts too soon.
Apogee's inaccuracies are well noted w/ LED's and other "broken spectrum" lighting..they jut get a tad more crucial w/ LED.

you may only have, say, a 10-15% under-sample..

I would be the first to admit I'm a bit anal on this point.
03-23-2015 08:07 PM
mba
Quote:
Originally Posted by jeffkrol View Post
Well it is an Apogee sensor.. w/ the same Apogee problem...



apogee is sure in no hurry to upgrade their sensor..

Jeff,

Can you clarify what issue of the Apogee sensor you are referring to? A newbie like me does not understand the chart you provided with the closed caption. I'm planning to use the new Apogee sensor to measure my LED custom photon 48 planted version from reefbreeders (I believe you helped me build that led light fixture last year and some other users).
03-14-2015 07:46 PM
Trigger334
My opinion

Hello, I'm a member here, but don't post to often. I have been thinking about PUR a lot lately, because we have been getting a considerable amount of people asking questions about the topic. (I work for a online aquarium store).

I made a video I thought covered the misconception of PUR, then discovered this thread when doing some more research about the topic.

Does anyone want to take a look at my video and see how they feel about PAR/PUR?

https://www.youtube.com/watch?v=-T4FKchXASs

Thanks for your thoughts!
03-14-2015 04:49 AM
mcarroll You can see a link above I posted (#365) a list of existing PAR<>lux conversion factors....just hoping someone with both meters would feel inclined to expand on that work. Have to admit it was worth asking! :-)

Now back to successfully using a lux meter to set up lights in place of a PAR meter...
This thread has more than 15 replies. Click here to review the whole thread.

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


All times are GMT. The time now is 05:26 AM.


Powered by vBulletin®
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Copyright Planted Tank LLC 2012