# here is the light chart some of us members talked about at todays meeting.



## fishyjoe24 (May 18, 2010)

credit goes to hoppycalif, and his p.a.r. meter... this is his chart.










Photosynthetically active radiation, often abbreviated PAR, designates the spectral range (wave band) of solar radiation from 400 to 700 nanometers that photosynthetic organisms are able to use in the process of photosynthesis. This spectral region corresponds more or less with the range of light visible to the human eye. Photons at shorter wavelengths tend to be so energetic that they can be damaging to cells and tissues, but are mostly filtered out by the ozone layer in the stratosphere. Photons at longer wavelengths do not carry enough energy to allow photosynthesis to take place.

Other living organisms, such as green bacteria, purple bacteria and Heliobacteria, can exploit solar light in slightly extended spectral regions, such as the near-infrared. These bacteria live in environments such as the bottom of stagnant ponds, sediment and ocean depths. Because of their pigments, they form colorful mats of green, red and purple. These organisms must make use of the leftovers discarded by the plant kingdom.

Typical PAR action spectrum, shown beside absorption spectra for chlorophyll-A, chlorophyll-B, and carotenoids 
Chlorophyll, the most abundant plant pigment, is most efficient in capturing red and blue light. Accessory pigments such as carotenes and xanthophylls harvest some green light and pass it on to the photosynthetic process, but enough of the green wavelengths are reflected to give leaves their characteristic color. An exception to the predominance of chlorophyll is autumn, when chlorophyll is degraded (because it contains N and Mg) but the accessory pigments are not (because they only contain C, H and O) and remain in the leaf producing red, yellow and orange leaves.

PAR measurement is used in agriculture, forestry and oceanography. One of the requirements for productive farmland is adequate PAR, so PAR is used to evaluate agricultural investment potential. PAR sensors stationed at various levels of the forest canopy measure the pattern of PAR availability and utilization. Photosynthetic rate and related parameters can be measured non-destructively using a photosynthesis system, and these instruments measure PAR and sometimes control PAR at set intensities. PAR measurements are also used to calculate the euphotic depth in the ocean. PAR is normally quantified as µmol photons/m2/second, which is a measure of the photosynthetic photon flux (area) density, or PPFD. PAR can also be expressed in W/m2. W/m2 measurements are important in energy balance considerations for photosynthetic organisms. Because photosynthesis is a quantum process, PPFD is generally used by plant biologists.

next question, would you like to have a par meter to use among members to test your lighting to tell you if you have low, low medium, medium, medium high, or high lighting... would like to see how much light you have when your bulbs are 6 months old, in 12 months? would you like to see how a hagen glo compares to a coralife, or a uv, or ati ? not all bulbs are equal.. and produce the same 6,700k colors...

will will raise a question for yes lets get a p.a.r. meter or i would like to see us get something else as a club..


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## niko (Jan 28, 2004)

I guess the table above is for bulbs that make sense to be mounted over a certain size tank. A 4' tank gets a 4' bulb (not a 2' bulb or 3' bulb). That information is not stated but I guess it makes sense to be that way.

The PAR measurements we will be taking will probably prove that an LED fixture is good for a planted tank ONLY if it has leds that cover the 400-700 wave lengths. I have an LED gizmo that is exactly that - only leds that make the plants go to town. But the light appearance is horrible - it is literally purple. So on top of a special mix of leds a planted tank LED fixture needs to also have leds that make the light look good to the human eye. It may turn out that an efficient LED fixture is not just slapping some powerful leds together. It may turn out that T5HO are and will be a much more reasonable choice. Except for the lack of underwater shimmer, which, being prominent in Michael's 10 gallon window tank made me stop breathing.



--Nikolay


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## fishyjoe24 (May 18, 2010)

actually led's work for a saltwater tank it has to have a lot of color combo my friend wayne who owns custom reefs in richardson off arapho and grove is putting leds over his 90g, and builds custom led lighting... /any way back to the chart, yes from my understanding is a 4 foot tank looks to get a 4 foot bulb.. i think it is more of a straight up down think as to how far each bulb was from the surface of the tank... hoppy is on apc as hoppycalif and ask him...


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## fishyjoe24 (May 18, 2010)

here is a contract that might need some twiting but might work.. :bored: 


Club Equipment Guidelines Summary:
Dfwapc maintains a PAR Meter or other equipment as part of the Society’s inventory for use by Premium(PAIDED) Members. Any BOD can be the "Holder" of the equipment. A sticky will be created in the dfwapc forum for equipment usage by members. The thread will track which BOD (board of directors) or Member has the meter or which Premium Member it is currently checked out to. An associated document (spreadsheet or checklist) will track current status and fees (Deposit & Late Fees) collected or returned. It will be the responsibility of the BOD Member who loaned out the equipment to track and report on its current status. The equipment will be marked as “Property of Dallas ft.worth aquatic plant club”. A photo of the device, the device serial number and “property of” will be taken for use in the event Dfwpc decides to take out insurance on the item and for proof of ownership for any subsequent Police reports that need to be filed.(I hope that never happens) The holder of the equipment may rotate (across all BOD Members) so that the equipment is available to different geographical areas.

Deposit:
$20 deposit (Cash Only) to be held by the BOD Member who loans the Equipment out.

Check out Procedures:
Must be a Paided Member/or trust person a member knows of Dfwapc and all current contact information must be on file with the Membership Chair and provided to the BOD Members during checkout.
Premium Member will make and inquiry as to which (BOD Member) has the Equipment.
Premium Members can check out the equipment and it is the member’s responsibility to go get the equipment from and return it to the same BOD member he/she gave their deposit to.
Check out period is one week (7 days).Check out Agreement will be completed and held on file

Late Fees & Penalties:
After 8 days a late fee of $5 will be assessed.
After 15 days a late fee of $15 will be assessed
After 22 days the device will be considered stolen and the appropriate reports will be filed unless Dfwapc receives a communication from the current holder of the Equipment that they intend to return it in a timely manner and pay all associated late fees.
Any member not returning the meter in accordance to the above guidelines can have their membership in Dfwapc suspended or revoked.

Return Procedures:
The Premium Members who check out the Equipment must return it to a BOD Member he/she got it from.
BOD Member will refund the $20 deposit and assess any late fees according the Late Fee Schedule.
Checklist or spreadsheet will be updated that the meter is again available for loan.

================================================== ======
Check out Agreement:

Item being checked out: ________________________________________________

I (Full Name)_________________ understand the terms and conditions of renting the equipment provided by DallasMAS for it members to borrow with the intent of returning it back in the same condition it was given to me. 
(Initials)__________ $20 Cash Deposit 
(Initials)__________ First Week is free. Second Week is a $5 late charge. 3rd Week is $15 late charge. 4th Week will result in suspension of membership privileges until returned.
(Initials)__________ Returned to the same person they borrowed it from.
(Initials)__________ I acknowledge that I will be held financially responsible for the equipment until it is returned back to the club in same condition as it was when checked out.

Disclaimer and Hold Harmless Agreement:
I specifically waive, release, indemnify and hold Dallas ft.worth aquatic plant club (hereafter "DFWAPC") harmless from any claim of any nature whatsoever for liability, personal or bodily injury, property damage, or harm to the environment that may be brought by me, my heirs, representatives, successors, customers, transferees, or any government agency, for any such liability, injury, damage, or harm arising out of my use/misuse or transfer to another of the items I use or received from dallas ft.worth aquatic plant club.

I have read and fully understand the statements made above and acknowledge the conditions under which the item(s) is being received. 

Signed: ___________________________ Print Name: ________________________________
Date: ___________________________


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