SantaMonica
Well-known member
Wow an algae wheel. Have not looked at those in years.
Algae Scrubber Advanced
- Thread starter maglofster
- Start date
Mike Edwards123
New member
Algae Scrubber Advanced
Yeah. It's by a company that is no longer in business. Aquatic Engineers. May not be as small as today's waterfall ats but the tank runs on only an air pump and lights. No impellers. It creates a surge as well although not enough of one. I am also converting my 90 gal reef tank to a 125gal and will be setting up a waterfall ats on that.
Yeah. It's by a company that is no longer in business. Aquatic Engineers. May not be as small as today's waterfall ats but the tank runs on only an air pump and lights. No impellers. It creates a surge as well although not enough of one. I am also converting my 90 gal reef tank to a 125gal and will be setting up a waterfall ats on that.
Brummie
Member
I've re-visited the Adey 3D screen theory. My conclusion is that if you have a submerged screen then the algae acts as substrate for diatom growth (and other epiphytic algae), increasing biomass. Now I look back at the article in question, Adey did elude to this. So here's a pic (changed lighting also to a blue spectrum, to simulate 5 metre water depth).
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Brummie
Member
Algae Scrubber Advanced
I know I've only used a cheap ipad app but I've measured the light intensity of an LED growlight 36w (3watt diodes) at a distance of two inches from the light source and it peaks at 1600 ft candles. Now, considering over 1200ft candles appear to be detrimental even dangerous to growth should we at least agree a maximum of 1200ft candles. This reading is without lenses.
Edit - Hmmm - now I've checked a CFL 23watt (with diy reflector) and it's upto 1800ft candles at 2 inch, needs to be 4 inches to get to below 1200ft candles.
I know I've only used a cheap ipad app but I've measured the light intensity of an LED growlight 36w (3watt diodes) at a distance of two inches from the light source and it peaks at 1600 ft candles. Now, considering over 1200ft candles appear to be detrimental even dangerous to growth should we at least agree a maximum of 1200ft candles. This reading is without lenses.
Edit - Hmmm - now I've checked a CFL 23watt (with diy reflector) and it's upto 1800ft candles at 2 inch, needs to be 4 inches to get to below 1200ft candles.
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Floyd R Turbo
Either busy or sleeping
I'm not sure if foot-candles is what you want to measure. You want to measure radiant flux, as this does not depend on human perception.
Brummie
Member
Algae Scrubber Advanced
I'm probably comparing apples with pears anyway. Quite how LEDS relate to white light output is beyond me, although my initial thoughts would be that LED power output should be considerably less than that experimentally shown to be inhibitive to growth in white light as nearly all the LED output can be utilized but only a fraction of white light is available to chl a, b. There are the accessory pigments to consider in white light though, along with cryptochromes, neochromes and phytochromes.
I'm probably comparing apples with pears anyway. Quite how LEDS relate to white light output is beyond me, although my initial thoughts would be that LED power output should be considerably less than that experimentally shown to be inhibitive to growth in white light as nearly all the LED output can be utilized but only a fraction of white light is available to chl a, b. There are the accessory pigments to consider in white light though, along with cryptochromes, neochromes and phytochromes.
Pny
New member
I guess the hydroponics guys are growing plants and not algae? Not sure if their knowledge is applicable here... Its obvious that they talk about absorption of chlorophyll b, since chlorophyll a has its absorptions peak at 665 nm. Do we know if the algae we grow in the scrubbers use chlorophyll a or b, or both?
Floyd R Turbo
Either busy or sleeping
I was told that 630s would be better because they output about 3x the intensity of 660s, and for plant growth they were by far the better way to go when looking at output radiant power per unit of input watt.
But so far in the real world, this does not hold true for algae. I believe this is both due to intensity and spectrum.
From my studies, I found that the chlorophyll A spectrum is used during times of intense sunlight, and the chlorophyll B spectrum is used during cloudy times, sunset, sunrise, etc. So B is sort of a 'backup' when A isn't available. I can't recall where I read that though.
But so far in the real world, this does not hold true for algae. I believe this is both due to intensity and spectrum.
From my studies, I found that the chlorophyll A spectrum is used during times of intense sunlight, and the chlorophyll B spectrum is used during cloudy times, sunset, sunrise, etc. So B is sort of a 'backup' when A isn't available. I can't recall where I read that though.
salty joe
Active member
Little bits and pieces I've picked up from you guys makes me wonder if blue has not been a winner because it's been too intense.
Based on the wavelengths plants utilize, I have a real hard time believing blue would not grow algae quite well. Especially since blue is generally considered for vegetative growth and red for flowering.
Based on the wavelengths plants utilize, I have a real hard time believing blue would not grow algae quite well. Especially since blue is generally considered for vegetative growth and red for flowering.
Brummie
Member
Wasn't all red before, it was a cheap red/blue led combo. The new pics are MH, yes. Although MH are less efficient I'm just testing the light, with a view to broad spectrum LEDS and not just red or red/blue combos. So far, I see more epiphytic diatom growth at day 7 but overall growth is similar to high red to blue ratios.
Brummie
Member
Algae Scrubber Advanced
I've been doing a bit of digging around on light intensity;
http://reefcentral.com/forums/showthread.php?t=2424221
If anyone has pertinent info then please add.
I've been doing a bit of digging around on light intensity;
http://reefcentral.com/forums/showthread.php?t=2424221
If anyone has pertinent info then please add.
Floyd R Turbo
Either busy or sleeping
Looks like we're on the way to a better way of looking at lighting and scrubbers
herring_fish
Crazy Designer
I’m a design engineer so I should know math and stuff but this makes my head hurt.
Seriously, I went to review my old calculations and ran across this somewhat dated chart from Dr. Adey’s book. The red lines and conversion was just there for my particular tank. Please ignore them. His chart was what he actually used in his setups. The lights appeared to be a few inches away from the screens, 3 or better.
One thing to note is that his studied assumed the scrubber was a 3-D scrubber with wave turbulence which is, according to his studies, 50% more efficient than those that do not have this type of design.
These designs allow for better respiration along with mineral and nutrient uptake over a longer time period. As harvest period approaches, in other designs, his observations might change quite a bit.
Die off might start earlier if metabolism is revved up that much. As flow to the individual strands begin to decay, respiratory distress might start earlier and be worse than normal. This could affect your average net uptake.
What I’m thinking is that if you use those higher light levels, you might need to be sure that you clean the screen promptly on schedule.
Brummie
Member
Algae Scrubber Advanced
I agree. When the filamentous stuff is present, the algae acts as the 3D substrate. On Adeys manufactured 3D screens he merely tried to emulate the algal mats where they were absent in Dino dominated systems. Lights been increased for a couple of days now and it certainly seems to have filled out (15 days in total)
I'm a design engineer so I should know math and stuff but this makes my head hurt.
Seriously, I went to review my old calculations and ran across this somewhat dated chart from Dr. Adey's book. The red lines and conversion was just there for my particular tank. Please ignore them. His chart was what he actually used in his setups. The lights appeared to be a few inches away from the screens, 3 or better.
One thing to note is that his studied assumed the scrubber was a 3-D scrubber with wave turbulence which is, according to his studies, 50% more efficient than those that do not have this type of design.
These designs allow for better respiration along with mineral and nutrient uptake over a longer time period. As harvest period approaches, in other designs, his observations might change quite a bit.
Die off might start earlier if metabolism is revved up that much. As flow to the individual strands begin to decay, respiratory distress might start earlier and be worse than normal. This could affect your average net uptake.
What I'm thinking is that if you use those higher light levels, you might need to be sure that you clean the screen promptly on schedule.
I agree. When the filamentous stuff is present, the algae acts as the 3D substrate. On Adeys manufactured 3D screens he merely tried to emulate the algal mats where they were absent in Dino dominated systems. Lights been increased for a couple of days now and it certainly seems to have filled out (15 days in total)
Brummie
Member
Algae Scrubber Advanced
This lot used 400w MHs x 2 and got readings double the readings I got (on a large screen) so I'm quite content that the calculations I've made are vaguely correct.
Page 77, 78 (actual page numbers)
http://drum.lib.umd.edu/bitstream/1903/10392/1/Blersch_umd_0117E_11236.pdf
This lot used 400w MHs x 2 and got readings double the readings I got (on a large screen) so I'm quite content that the calculations I've made are vaguely correct.
Page 77, 78 (actual page numbers)
http://drum.lib.umd.edu/bitstream/1903/10392/1/Blersch_umd_0117E_11236.pdf
