My AGA talk about light and CO2 demand

[krandall]

That's right, Tom. It's not that he disagreed with you that was the problem... it was that he wouldn't let it go, in the context of the lecture. It wasn't HIS lecture, it was YOURS. It would have been FINE if he had talked to you (or even debated with you) later. But during the Q&A for the lecture wasn't the time or the place. Not only was it disrespectful, but it was keeping other people from asking questions that were of interest to them.

Which reminds me... sometime we need to talk about my diagram... which is not a venn diagram. A agreed with most every thing you said, and you gave me some things to think about. It's just your memory that needs tweaking!

 

[jerrybforl]

I thought the guy was way out of line as well. We are all hobbyists not experts. We gain knowledge over years of experience, but there is always something to learn. He would've been better off talking to Tom afterwards.

I think Tom has a wealth of information, and I'm glad that I've been able to pick his brain a little bit!

 

[Tom Barr]

That's right, Tom. It's not that he disagreed with you that was the problem... it was that he wouldn't let it go, in the context of the lecture. It wasn't HIS lecture, it was YOURS. It would have been FINE if he had talked to you (or even debated with you) later. But during the Q&A for the lecture wasn't the time or the place. Not only was it disrespectful, but it was keeping other people from asking questions that were of interest to them.

Which reminds me... sometime we need to talk about my diagram... which is not a venn diagram. A agreed with most every thing you said, and you gave me some things to think about. It's just your memory that needs tweaking!

My memory is great, but it is very limited to specific things, and the diagram was not one of them
When I saw the talk, you had 3 circles, and they over lapped like this:

http://en.wikipedia.org/wiki/Venn_diagram

In the middle, like the Latin, Greek and Russian alphabets.........were CO2, light and nutrients.
That's what I recall. Now that was 1998 or thereabouts(could be wrong here as well). So close to 15 years lost between the ears.

Feel free to correct my bad memory. Did I just open a big can O worms?


Good news is, I spoke with him later. It was hardly anything like the talk's Q&A.
Always some good questions.

I like being grilled personally.

 

[krandall]

My memory is great, but it is very limited to specific things, and the diagram was not one of them
When I saw the talk, you had 3 circles, and they over lapped like this:

http://en.wikipedia.org/wiki/Venn_diagram

In the middle, like the Latin, Greek and Russian alphabets.........were CO2, light and nutrients.
That's what I recall. Now that was 1998 or thereabouts(could be wrong here as well). So close to 15 years lost between the ears.

Feel free to correct my bad memory. Did I just open a big can O worms?


Good news is, I spoke with him later. It was hardly anything like the talk's Q&A.
Always some good questions.

I like being grilled personally.

Nope. Never used a venn diagram. I know what they are, but I can't figure how you'd make it work talking about these concepts. This is first is the one I used even back in "slide days"... I actually had it made into a slide, (remember what those were?) and I didn't do that often because it was hard work and expensive. The second one is what I (finally) upgraded to in 2009, when PowerPoint and Photoshop made things SO much easier. A little "slicker" but still the same concept. I don't remember when I first spoke in SF. Were we still using slides then, or had we moved on to PowerPoint? If it was '98, it was probably still old style slides, because my earliest digital images start in '99, and were sparse those first few years.

While I don't think I made the point as succinctly as you did about light "driving" the system, (and I'll "borrow" that phrase in the future) I think the slide does illustrate that IDEA pretty well. In my talks, I have always gone on to explain that you can "balance" things at a lower/slower rate with low light, or at a high power rate with high light, but that you need to balance the CO2 and nutrients added to the tank based on the amount of light. I think we are saying pretty much the same thing.

One BIG difference between now and the early days is that it was close to impossible to drive the system "too" fast back then, just because it was impossible to stuff enough T12 fluorescent tubes over a tank to get the light levels we have (easily) available today. And lighting just keeps getting more complicated. The LED's are a whole new kettle of fish. In the early days, the common advice was that it was hard to have "too much". Nowadays, "too much" is pretty easy.

I'm glad that you and that guy had a fruitful conversation later... he obviously left a bad taste in many people's mouths right after your talk.

 

[Tom Barr]

I am becoming feeble minded to be certain. The triangle of sway is certainly good as well.

Yes, slides suck.
Colors and details are nicer though.

I think "driving" the system is one more biochemical or enzymatic way to look at photosynthesis.
It is a pathway. The End result is hopefully, plant growth. Yes, we say the same things, but tell a it differently.

Yes, we just did not have enough light back in those days really and few had PAR meters.
I used the Hamiliton MH's and had really high light on my 90 Gallon tank.
That was about as high as it got back in the 1990's.

The leaner dosing and lower CO2 from back in those days..........reflected the lower light most had.
Those same ppm's and CO2 persisted with many people even till this day.
Even though they added 2-4x as much light
That's wasteful and asking for more work and headache.

That's not a "balanced" view/philosophy frankly. With the pathway, you can show that pretty easily.

As Caesar once sad: "people freely believe what they want to believe, not what is the truth".
Like me, and those Venn diagrams, hehe.

LED's are a troublesome complexity. They can be very point source like MH's, or they can have many many tiny smaller sources that come closer to a FL tube, we say those from A&H supply and from Finnex at the AGA meeting.
Those where impressive and better than many of the Cree 3 W DIY projects. I did a couple DIY Cree's, but I've not been happy with the evenness of the light spread or the colors from the plants. The DIY and the Cree generally are nice for the reefs.
I use them there.

I use only 1.2 W/gal of T5's on this 350 Gal nature style tank:

Another tank is 28" deep and the lights are 18-20 inches above the water's surface, well over 1 meter away.
This uses a pair of TEK fixtures, the ATI fixtures would add about 50% more light.


I can double the lighting, but then the Gloss becomes really weedy. The light in this tank is pretty close to the ADA tank's averages as far as PAR.