Daily Light Integral, PAR, and Photosaturation Discussion

[saltyfilmfolks]

Thanks for this a lot to read and re read in here and help a lot as there is only what other successful people have done with time periods and lighting over there tank. I need a bigger calculator

No sweat.

I pretty much just had to take off my shoes to count that high.

 

[justingraham]

So u have a lot of toes as well??

 

[saltyfilmfolks]

No, they are all just big.

 

[saltyfilmfolks]

Wow! Lots of great info here already, let's keep it going

So now that you've poured over the material, what do you think this information will do for you to improve your reef? Or how would you implement it to make changes?

 

[Scrappy RN]

Newby question here: I understood the discussion of PAR and DLI but then someone threw a wrench in with a suggestion for a LUX meter! Exactly what does that measure?

 

[saltyfilmfolks]

Newby question here: I understood the discussion of PAR and DLI but then someone threw a wrench in with a suggestion for a LUX meter! Exactly what does that measure?

Intensity of light. Or , how bright it is. (You may have also heard of foot candles)

A light can have a lot of intensity , but relatively low par. Like a light bulb in your house. It can be measured both with a Lux meter for intensity or a par meter that measures both the spectrum and the intensity together.

A good light with good spectrum for corals can therefore be measured with a Lux meter and the results estimated for the approximate par , this is a Lux par conversion.
https://www.apogeeinstruments.com/conversion-ppf-to-lux/

So by increasing the intensity(dimmer for example) the par naturally increases.


For most leds the Lux par conversion constant is about 60 at the native color (1:1 w/b or all on evenly).

 

[Scrappy RN]

Ok, thank you!

 

[saltyfilmfolks]

Ok, thank you!

Your welcome !

 

[Dana Riddle]

Not necessarily layman terms, just trying to open up a discussion to hear about people's experiences with DLI, etc. Although, layman terms aren't so bad sometimes!



JUST A QUICK QUESTION! PLEASE EXPLAIN QUANTUM MECHANICS! lol

I'm excited to see folks post about their DLI numbers and what sort of success they are having.

Would you mind going into a bit more detail on water motion? Specifically, velocity? How does that apply to total GPH measurements vs. random flow patterns, etc?



Where in Georgia are you located? We do have some great shops here! I'm in Lawrenceville.

I'm in Dallas, Georgia. There's a pretty good shop about 30 mins. away on Powder Springs Road. I joined the Atlanta Reef Club and. minutes later. won a $50 gift certificate. I'm cycling a small system now, so hoping to use the certificate in the next couple of weeks!

 

[Flippers4pups]

Defiantly interesting reading. Going take sometime to digest. Adds to the complexity of understanding what coral need, but this is where we are heading and it's needed. It's leaps and bounds from where I started back in 93.

 

[Dana Riddle]

This might help if you have an older Apogee meter, or other.
http://www.advancedaquarist.com/2013/2/equipment

 

[Flippers4pups]

This might help if you have an older Apogee meter, or other.
http://www.advancedaquarist.com/2013/2/equipment

Thanks Dana for the link. I have read this one, as most of your articles. Your presentation at last years Macna was reaffirmation of my own experiences with alkalinity and flow in my own reef systems over the years, minus the information on light intensity. That was done up until recently by eyeball and how corals would react to placement.

I have no par meter, but do have a calibrated extech easyview 30 lux meter that I've used to measure my lights, via the conversion to par information you and #saltyfilmfolks have provided. Thank you!

It helped me verify my light intensity to achieve the 100-250 par throughout my DT. I didn't need to adjust them much. (I guess my eyes are still calibrated after all these years! Lol)

DLI and nutrient consumption is now my focus. Has there been any research on uptake of nutrients in correlation to photosynthesis, based on your studies of alkalinity, flow and light intensity?

 

[Dana Riddle]

Thanks Dana for the link. I have read this one, as most of your articles. Your presentation at last years Macna was reaffirmation of my own experiences with alkalinity and flow in my own reef systems over the years, minus the information on light intensity. That was done up until recently by eyeball and how corals would react to placement.

I have no par meter, but do have a calibrated extech easyview 30 lux meter that I've used to measure my lights, via the conversion to par information you and #saltyfilmfolks have provided. Thank you!

It helped me verify my light intensity to achieve the 100-250 par throughout my DT. I didn't need to adjust them much. (I guess my eyes are still calibrated after all these years! Lol)

DLI and nutrient consumption is now my focus. Has there been any research on uptake of nutrients in correlation to photosynthesis, based on your studies of alkalinity, flow and light intensity?

Not surprisingly, fertilizing nutrients are thought to increase the number of zooxanthellate or perhaps chlorophyll content. It is unknown (to me) if this will increase the rate of photosynthesis although I think we can say that the gross amount of photosynthesis will increase. However, things such as zoox self-shading, altered compensation and saturation points due to light intensity muddy the waters so I can't make a definite statement. The lab is close to completion so it will soon be relatively easy to manipulate nutrients and monitor chlorophyll content and electron transport rates.

 

[Greg Esmond]

This is a great thread!

I have a question about the "peak period" you guys use. Have any of you tried manipulating the "peak period" based on motion sensors in the room? Basically, instead of the peak period occurring in one block of time at the same time every day, have you tried activating shorter peak periods throughout the day whenever motion sensors are triggered? I ask because I like the way my aquarium looks at the higher light level, and would really like to see that every time I walk through the room.

The algorithm for such a behavior could be as complicated as someone wanted to make it, but it seems that it could be kept pretty simple without impacting the corals. If you know what your DLI should be, and you have a power usage monitor on your lighting system (like the TP-Link HS110), then it seems trivial to convert DLI to kWh per day, and control the ramp-down based on each day's consumed kWh. Basically, if motion detection triggers a lot of peak period usage early in the day, then the ramp-down could start earlier. Alternatively, on days with very little motion detection, the peak period(s) could be pushed later in the day with a shorter ramp-down.

I just added this functionality to my system by integrating my Phillips Hue motion sensors into my fish lighting controls in Node-Red, and I love it! However, I don't have a PAR meter, LUX meter, and don't have any idea what my DLI should be. Right now I'm just targeting a daily kWh, and plan to adjust it up or down based on the coral's response.

That said, if any of you guys can recommend a decent / affordable PAR and / or LUX meter, I'd buy them.