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Thread: PAR vs Distance, T5, T12, PC - New Chart Reply to Thread
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  Topic Review (Newest First)
06-11-2014 10:36 PM
Originally Posted by lauraleellbp View Post
Want it locked, Hoppy?
Yes, please!!!!
06-11-2014 04:21 PM
lauraleellbp Want it locked, Hoppy?
06-11-2014 03:56 PM
Hoppy This is an obsolete thread. I suggest reading and using for much more accurate and up to date information. (That thread will also be obsolete as more information is available, as more people post their light measurements for various light fixtures, and as we all learn more about the subject.)
06-10-2014 06:17 PM
801boom Great read
12-26-2013 10:03 PM
Raymond S. I have a T5HO two bulb fixture on a ten G tank. It is borderline too high. Didn't read all the comments to see but would
like to make an observation that in other post where questions are asked from a viewpoint of "I have T5's and don't see the growth
that I think should come from their use so can someone help me/w this ?" In some of those Threads it is mentioned that
ANY glass cuts down on how much light you have reaching the plants and especially if there is any dust/calcium deposits/water
stains on it. Perhaps this is the reason that I don't see any serious amount of excess light in my tank/w the two T5HO bulbs
in there. I do use Excel as directed by the label so if I stopped using it as I plant to, I'd likely be over run by algae.
Probably only fair to mention that there is hair algae in my tank as well as green spot on the rocks which I placed on the walls
for it to cling to. The algae is not "taking over" but cultivated as part of a "natural" environment type tank with a direction in
mind as to a specific end result later after a sufficient amount of plant growth is obtained. i.e. Cut off the Excel and increase the
percent of the Giant Duckweed growing on the top to control the light/growth level.
10-04-2013 11:55 AM
Originally Posted by Mizuhuman View Post
zanguli, this thread is considered obsolete by its creator, Hoppy
You should read the more up-to-date thread below
I hope this can answer your questions
Hi Mizu

Thank you very much I will post in this link.
have a good day

10-04-2013 04:19 AM
audioaficionado Perhaps Hoppy can ask a mod to lock this thread.
10-03-2013 09:36 PM
Mizuhuman zanguli, this thread is considered obsolete by its creator, Hoppy
You should read the more up-to-date thread below
I hope this can answer your questions
10-03-2013 11:42 AM
zanguli Hi members,
how are you ?

First thanks to Hoppy to bring out this chart that is very useful. I have discover this forum by this thread, an expert member of an other forum linked me this thread that is very very interesting. so every one thanks for you input in this topic.
after reading the 52 pages (that was very long but food for brain) I am a bit confuse now haha.
Let me explain.
Tank : 90x45x50 cm
Light : NA SunFluor 4x36W osram PC hanging at 20" from the substrate
reflector is a very high polished aluminum.
the tanks is only 3 weeks old so I turn on only two bulbs.
Pressurize C02

After reading all the topic I have discover that PC gives a lower PAR reading than T5HO.

My concern is that maybe with only two PC bulb of 36 W at that height I will be too low in PAR (Tom Barr said in this topic that the limit range for most of the plant (not low light plant) will be 25-30).
So I am just afraid that maybe with this configuration I might be too short ?

If I follow the graph with one PC bulb at 20" I will have a PAR +/- 20 so for two I will have PAR 40, Is that right ?
In fact I would like to grow a HC carpet (I have fail many time with it) I truly know that HC is a CO2 lovers and need good distribution down to the carpet to achieve a good carpet, but with that amount of light am I in the good zone to grow it, am I not too short on light?
Would you advice me to stay in this configuration until the tank is mature and plant have made the transition, or I should turn the third bulb for the HC. I don't want to push the too high for now to be sure that HC will do the transition and not melt due the higher demand of CO2 that stronger light will thrive.

Sorry if my post is a bit confuse but it reflect my state of mind hahaha.
I wanted also to apologies if I have mad grammatical and other language mistakes, but english os not my language.

thank you very much for you help.
08-12-2013 09:41 PM
Allentan97 nvm... lol i just realized that this thread is old.. no 600 par for me, lol
08-12-2013 11:10 AM
T5NO Single Bulb Data Point

I have a 50 gal 18" high tank with 2" of substrate. My T5NO bulb is 2.5" from the water level. Par value is 42 +/-3 depending on where on the substrate the measurement is taken.
08-12-2013 05:12 AM
Allentan97 ummm..... soo i have like 600 par? what??? thats A LOTTTTTT of light.... lol 2 t5ho coralife fixture, 10 inches away at most. 6 at the closest.... hahaha 600 par
07-06-2013 01:16 AM
Hoppy This thread is obsolete! See for more up to date information, which will before long be obsolete too.
07-05-2013 05:26 PM
colin I can't help but to post... this was one of the msot useful things I have ever seen posted on any aquarium forumn, thanks so much for doing the work! I way over lit my last tank, and surprise surprise, algae! I almost got a 6 bulb T5HO fixture for my 75 gal tank. Overkill!
11-21-2012 01:25 AM
Bryanmc1988 need an answer fast... do you think 1 t5 40 watts is more then enough to grow dwarf baby tears in a 40 gallon breeder tank with decor and rocks etc, it comes out to about 30 gallons of water only... let me know i am looking to redo my lights right now... 2 bulb or 1 for this tank

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