Algae Scrubber Basics

[herring_fish]

I am dictating this from my phone so please bear with me. I'm wondering if there has been much progress determining how much difference there is between the different wavelengths in lighting. The reason I ask is that if there isn't much difference then I could use all blue LEDs since the light from my scrubber bleeds into the main tank. This would contribute to a better look but I might loose lots of efficacy.

Has there been any one that has shown a difference in the efficacy of export with red-plus blue as opposed to blue only or as opposed to 2700K etc.

Thank you

 

[_shorty_]

Thanks for that, Are your Led's the Bridgelux ones

I don't think they were Bridgelux brand... I think mine were probably chinese made. They were like $24 or $25 each on ebay.

 

[_shorty_]

I am dictating this from my phone so please bear with me. I'm wondering if there has been much progress determining how much difference there is between the different wavelengths in lighting. The reason I ask is that if there isn't much difference then I could use all blue LEDs since the light from my scrubber bleeds into the main tank. This would contribute to a better look but I might loose lots of efficacy.

Has there been any one that has shown a difference in the efficacy of export with red-plus blue as opposed to blue only or as opposed to 2700K etc.

Thank you

I don't recall reading anyone report back that tried all blues, actually. People do say they are going to try every once in a while.

I believe most of the data comes from basic photosynthesis principals and tests... which is the same reason why most grow bulb LEDs are now Red with a small amount of blue. Google 'photosynthesis wavelength' and you'll find graphs that show the peak light absorption wavelengths. My guess, is that it'll grow algae, but it probably wouldn't be optimal.

Blue is absorbed easier than the red according to charts.. which I believe is why the Red:Blue ratio is 5ish:1. Floyd even recommends running blues at half intensity/parallelled if you DIY. So it tends to be easier to 'oversaturate' or burn out (create hot-spots) your algae with all blues. You might be able to play with different light cycles to optimise this though. I'm speculating, of course.

A friend worked on construction site at a college a while back that was studying this. They were growing corn - one in daylight lighting, the other in Red with blue lighting. He said the Red:blue (he called it pinkish purple) was several feet taller than the daylight lit corn.

This doesn't answer your question as to all blues.. but it's interesting.

 

[SantaMonica]

I've seen a few people try all-blues, and it did not grow at all.

 

[Editour2]

Soliciting opinions: I did not read through this whole thread...it is voluminous (but will if I have to). My system is a total volume of approximately 350 gals, (215 DT w/sump, refugium and frag tank). I have high phosphates and high nitrates no matter what I do. So in deparation I am trying this scrubber. I have built two 11" x 16" scrubbers that are vertical and over my refugium (about 1" in the water). Flow will be around 750 gph. I have set up for 1 bulb on each side of EACH 11" x 16" plastic canvas sheet using clamp lights like this:
http://www.homedepot.com/p/Commercial-Electric-75-Watt-Incandescent-Clamp-Light-CE-200PDQ/100354513
I'd like to go with LED's as well and was thinking about the grow lights this forum is discussing. My question is:
What wattage would I need for my length of canvas sheets? I have the clamp fixtures set up approximately 4" from each sheet on both sides. I was thinking about the 54watts or perhaps 29watts:
http://www.ebay.com/itm/12RED-6BLUE...d=100011&prg=1005&rk=3&rkt=5&sd=171140238983&

Would want to use the most efficient because electric bills are already through the roof but of course want to cultivate algae. What's the consensus?
thanks

 

[mess7777]

However, if you are wanting to run heavy SPS, the word I have been hearing from scrubber users is that scrubber-only systems tend to lead to lack of PE (polyp extension) and browning of corals as the zooxanthellae appear to be overfed. So adding a small amount of carbon, or a skimmer and carbon, seems to make the PE return.

What interests me the most is why the PE declines. Theories abound. One of them is that since scrubbers do not remove food, the coral is fed well and the polyps don't need to extend. Increasing the light may cause better uptake and thus the need for more food? Dunno...thinking aloud.

Lack of carbon availability due to all the CO2 being removed by the scrubber? The addition of a skimmer would help gas transfer, and *may* be what is fixing the problem.

I am looking for more information on this. I have PE problems, particularly with millepora....and am running without a skimmer. I do run carbon, so I can testify that carbon alone is not the answer. I have a crappy skimmer, I guess I'll start it up and see what happens. If anyone has similar experiences and could share that would be awesome!

 

[Editour2]

screen is 12x12

also have a saran wrap over the screen for spray protection

Your screen is 12" x 12" and you are using the 12 watt LED bulbs? 1 on each side? I am asking because my screen is 11" x 15" (roughly the same) and don't know what wattage bulb would make the best sense.....

 

[Editour2]

The range I recommend is 1 660nm Deep Red LED on each side of every 4-8 square inches of material, at 2" distance from the screen. Run 9 hours/day initially and adjust from there as needed. I use a diffuser at 1" until there is enough growth to fill in the holes.

If you are using an existing screen, then you can probably skip the diffuser. Or, you could move the LEDs back an inch or two.

For a 7x8 screen = 56 sq in, then 56/8=7 LEDs, 56/4=14 LEDs, or you can go somewhere in between and throw in a few blues (either running at 1/2 current by wiring in parallel, or just by using 1W blues)

If you go for the minimum of 7 per side, you can use one meanwell-LPC-35-700 which will run 14 LEDs. Otherwise you need multiple drivers (or a different one)

HTH
Bud

Does this formula apply to 1 watt LEDs or 3 watt LEDs? If 3 watt then would each LED cover more square footage of screen?

 

[SantaMonica]

Lack of carbon availability due to all the CO2 being removed

Why would you want more carbon? The only carbon you want is food particles; not CO2.

Editour: Both those bulbs are going to be too focused/narrow, and are going to not deliver light to the whole screen. A larger 11" reflector with 44 watt spirals might be better; or two of the smaller ones on each side.

 

[Floyd R Turbo]

Does this formula apply to 1 watt LEDs or 3 watt LEDs? If 3 watt then would each LED cover more square footage of screen?

That is for 3W LEDs. For a very large screen, just shoot in the middle of that formula and call it good. So that would be 1 DR on each side of every ~6 sq in of material. You can try the lower quantity also, like every 8 sq in (or even 10) and see what happens. But if you go with the lower quantity make sure you drive them to 700ma.

 

[Floyd R Turbo]

Soliciting opinions: I did not read through this whole thread...it is voluminous (but will if I have to). My system is a total volume of approximately 350 gals, (215 DT w/sump, refugium and frag tank). I have high phosphates and high nitrates no matter what I do. So in deparation I am trying this scrubber. I have built two 11" x 16" scrubbers that are vertical and over my refugium (about 1" in the water). Flow will be around 750 gph. I have set up for 1 bulb on each side of EACH 11" x 16" plastic canvas sheet using clamp lights like this:
http://www.homedepot.com/p/Commercial-Electric-75-Watt-Incandescent-Clamp-Light-CE-200PDQ/100354513
I'd like to go with LED's as well and was thinking about the grow lights this forum is discussing. My question is:
What wattage would I need for my length of canvas sheets? I have the clamp fixtures set up approximately 4" from each sheet on both sides. I was thinking about the 54watts or perhaps 29watts:
http://www.ebay.com/itm/12RED-6BLUE...d=100011&prg=1005&rk=3&rkt=5&sd=171140238983&

Would want to use the most efficient because electric bills are already through the roof but of course want to cultivate algae. What's the consensus?
thanks

For an 11x16 screen (assuming a 16" is the vertical dimension) you'll need around 400 GPH of actual flow (after head loss) per screen.

For lighting, assuming that you will really have an active area of growth closer to about 10x12 but possibly as big as 11x14 you will want between 120 and 150 watts of CFL on the screen, split between both sides. That would be the minimum level of light. That's using big reflectors like SM mentioned and probably the biggest CFL you can find. Or you could do multiple CFL floodlights, in this case 4x23W per side would be better coverage - almost 100w per side.

If you go to the "high light" level and run them only 9 hours/day, you're up to 120W per side and that's getting crazy.

For LED, one per 8 sq in per side is 20 per side, 40 per screen. For high-intensity, double that.

Either way you cut it though, you're not going to need this scrubber to be this gigantic size for long unless you are feeding upwards of 20 or more cubes of food per day and have no other active filtration. Personally I think one screen would cut it in the long run, so maybe you pop for the LED array on one of the screens and make the other out of CFL so that you can just use it for the short term and then ditch it when it comes time to replace the lamps.

Plus it's going to take a few weeks (up to 6) for the screens to cure anyways, so you are going to have to continue with the PWCs until then.

I'm guessing that might raise a few more questions too. One thing, have you reviewed the feeding-based sizing guidelines? See the posts in my sig below

 

[Floyd R Turbo]

Also I forgot to cover that LED lamp you posted. The issue with LED floodlights is the same as CFLs. They do not cover a wide area, and the further away you put them, the less effective they are. You would be better to use a few smaller ones and have them closer than to use one big one and need to put it further away.

You might consider making several smaller scrubbers instead of one (or two) big ones. The CFL floodlight are good for a 6x6 screen, this larger one maybe an 8x8 screen. So instead of putting 4 of the smaller ones on each side of a 12x12 screen, do 2 8x8s with the larger one. Something along those lines. Make sense?

 

[Editour2]

That is for 3W LEDs. For a very large screen, just shoot in the middle of that formula and call it good. So that would be 1 DR on each side of every ~6 sq in of material. You can try the lower quantity also, like every 8 sq in (or even 10) and see what happens. But if you go with the lower quantity make sure you drive them to 700ma.

Based on my total system volume.....I calculated that I needed 2 screens that were 11"x16" which would cover my 350 gallons of water. (Each screen covers roughly 175 gals). Are you saying that I over estimated?

Not sure how I can drive LED bulbs to 700ma...........since they are plug and play.

 

[Floyd R Turbo]

You are using the old guideline, which was based on volume. The new guideline is based on feeding - 12 sq in of screen, lit on both sides, for every cube of food fed per day

 

[Editour2]

For an 11x16 screen (assuming a 16" is the vertical dimension)It is... you'll need around 400 GPH of actual flow (after head loss) per screen.
I have this covered....I am using a panworld pump that can generate approximately 1100gph....I have a ball valve installed to control the flow. The 2 screens are running along the same 34" 3/4" pvc but split into 2 x 12" slotted sections...I will try to post pics.

For lighting, assuming that you will really have an active area of growth closer to about 10x12 but possibly as big as 11x14 you will want between 120 and 150 watts of CFL on the screen, split between both sides. That would be the minimum level of light. You are saying 75 watts on each side for each screen?

That's using big reflectors like SM mentioned and probably the biggest CFL you can find. Or you could do multiple CFL floodlights, in this case 4x23W per side would be better coverage - almost 100w per side. Wow....let me get this straight ....the reflectors I posted, (from the Home Depot link), are too small to difuse the light properly? I belive they are 6" diameter.....I should use the 11" diameter reflectors with 100 watt bulbs or the smaller 6" reflectors x 4 for each side? Space and electricity are both a consideration here.....that would be 400 watts of electricity just for the lighting and I don't think I can fit 16 reflectors (2x4 on each side) in my space. I am setting this up over my 40 gal refugium which is 36"L x 18"H x 14" D (I think...I'll check those dimensions)...which limits my space. Also are you saying that the 54watt LED bulbs I posted won't work as well as the CFL bulbs because the light is too concentrated? Would that hold true with a larger reflector and maybe 120 degree LED lenses (which is an option from the manufacturer)?

If you go to the "high light" level and run them only 9 hours/day, you're up to 120W per side and that's getting crazy. For LED, one per 8 sq in per side is 20 per side, 40 per screen. For high-intensity, double that. I guess you are talking about DIY LED's here? OR possibly 4 x 54 watt LED bulbs each side, (2x bulbs for each screen on each side...which could get very expensive).

Either way you cut it though, you're not going to need this scrubber to be this gigantic size for long unless you are feeding upwards of 20 or more cubes of food per day and have no other active filtration. I currently run an Orca 200 skimmer and a BRS Dual reactor w/carbon and GFO yet my phophates are .5 (it was 1.09) and my nitrates are 3.0ppm. Regarding feeding...I do have around 20 fish and feed some flake or pellets in the morning and around 4 cubes at night (after rinsing in saltwater). Should I cut the scrubber size down to half right now before I complete this build?

Personally I think one screen would cut it in the long run, so maybe you pop for the LED array on one of the screens and make the other out of CFL so that you can just use it for the short term and then ditch it when it comes time to replace the lamps. I need to take action quickly because I'm loosing all my corals. Like I mentioned earlier space and $'s are a consideration however I want to be done with this high phosphates & nitrates issue and like to do things right the first time around.

Plus it's going to take a few weeks (up to 6) for the screens to cure anyways, so you are going to have to continue with the PWCs until then. PWC's???

I'm guessing that might raise a few more questions too. One thing, have you reviewed the feeding-based sizing guidelines? See the posts in my sig below

I will read that asap and thank you very much for your input...I will try to post pics tonight so you can visualize what I am doing.

 

[Floyd R Turbo]

PWCs = Partial Water Changes.

In response to your above post:

1) revisit the sizing guideline per feeding. Estimate how many cubes/day you are feeding. Calculate the appropriate screen size based on that, then double it. That is the largest screen you should really need. Based on your last post, I would estimate between 4-6 cubes/day is what you're feeding, so a 10 cube/day screen should be more that adequate. 120 sq in.

2) Algae scrubbers are not a quick fix, if "quick" means "right now, I'm losing my corals". you don't have time for an algae scrubber to fix that if that is happening right now. This is a long term solution. You need to build the scrubber, yes, but you also need to address the immediate situation which means you are probably going to have to do a series of PWCs, starting now.

3) 3ppm nitrates is nothing to worry about. Nothing. don't even concern yourself with 3ppm. Phosphate a 0.5 ppm, this is probably your biggest problem and could be the reason your corals are declining. The only way to get these down quickly is large PWCs and GFO. I would run Phos-Blast from Premium Aquatics instead of GFO. It is exactly the same as RowaPHOS. The only thing that is better (and not my much) is GFH (granulated ferric hydroxide) which is BRS's "high capacity GFO". Phos-Blast / RowaPHOS is good stuff.

4) you may end up going through a 'clean-up' stage if you have left your tank at high nutrient conditions for a while. This means that once the scrubber gets cured, and starts to really suck down the nutrients, another mechanism (not 100% clear what it is, but it appears to be chemical + bacterial action) can cause the release of bound waste from the rocks and sand. This means that you might get some algae and/or cyanobacteria outbreaks, but it will pass (how long depends on how dirty your tank is) and your system will be much healthier in the end.

5) For LED lamps like the one you are referring to, I would recommend 12 degree optics which will allow a wider spread and allow you to put the light closer without burning. Then remove the optics from the blues when you get it so that the blues are very spread out - you don't need much. Verify with the manufacture that this (removing lenses) will not cause the lamp to stop working.

6) if screen is 120 sq in, then you need 60W of CFL per side for normal light, 120 for high light.

7) for LEDs, at least for DIY fixtures, 120 sq in of screen would need 15 deep reds per side, or 30 for high light. Or anywhere inbetween. If going by wattage for a stock fixture, shoot for the higher number overall, and multiple lamps if you can. LED floodlights are not as effective on large screens because they group them too close and you do not get even coverage.

 

[Editour2]

PWCs = Partial Water Changes.Thanks !!!!

In response to your above post:

1) revisit the sizing guideline per feeding. Estimate how many cubes/day you are feeding. Calculate the appropriate screen size based on that, then double it. That is the largest screen you should really need. Based on your last post, I would estimate between 4-6 cubes/day is what you're feeding, so a 10 cube/day screen should be more that adequate. 120 sq in. I have 5 tangs so add a sheet of 8" x 14" nori 5 days a week. I am now thinking 2 x 10" x 10" Plastic mesh would suffice....I am reading your new summary.

2) Algae scrubbers are not a quick fix, if "quick" means "right now, I'm losing my corals". you don't have time for an algae scrubber to fix that if that is happening right now. This is a long term solution. You need to build the scrubber, yes, but you also need to address the immediate situation which means you are probably going to have to do a series of PWCs, starting now. I have doubled my water changes and I change my GFO/Carbon weekly since I noticed this problem...that's how I got the phosphates down to .5, which isn't low enough.

3) 3ppm nitrates is nothing to worry about. Nothing. don't even concern yourself with 3ppm. Phosphate a 0.5 ppm, this is probably your biggest problem and could be the reason your corals are declining. The only way to get these down quickly is large PWCs and GFO. I would run Phos-Blast from Premium Aquatics instead of GFO. It is exactly the same as RowaPHOS. The only thing that is better (and not my much) is GFH (granulated ferric hydroxide) which is BRS's "high capacity GFO". Phos-Blast / RowaPHOS is good stuff. I am running the standard BRS GFO.

4) you may end up going through a 'clean-up' stage if you have left your tank at high nutrient conditions for a while. This means that once the scrubber gets cured, and starts to really suck down the nutrients, another mechanism (not 100% clear what it is, but it appears to be chemical + bacterial action) can cause the release of bound waste from the rocks and sand. This means that you might get some algae and/or cyanobacteria outbreaks, but it will pass (how long depends on how dirty your tank is) and your system will be much healthier in the end. I am experiencing cyano outbreaks right now....my tank has been running for 2 years now and this just started happening about 2 months ago...it started when all of my GSP shut down and then began to melt away.

5) For LED lamps like the one you are referring to, I would recommend 12 degree optics Do you mean 120 degree optics?which will allow a wider spread and allow you to put the light closer without burning. Then remove the optics from the blues when you get it so that the blues are very spread out - you don't need much. Verify with the manufacture that this (removing lenses) will not cause the lamp to stop working. I could use the spiral bulbs if that is a better choice.

6) if screen is 120 sq in, then you need 60W of CFL per side for normal light, 120 for high light. I think that when I take the nori into account this will be too small. If I go with the 2 x 100 sq in then I guess the 60w per side would still work...Do they sell a 60 watt CFL bulb?

7) for LEDs, at least for DIY fixtures, 120 sq in of screen would need 15 deep reds per side, or 30 for high light. Or anywhere inbetween. If going by wattage for a stock fixture, shoot for the higher number overall, and multiple lamps if you can. LED floodlights are not as effective on large screens because they group them too close and you do not get even coverage.

Wow....I should have waited before I jumped in and starting building this....alot more involved then I first thought.....I need to finish reading your new basics summary and re-check calculations (besides bringing back some stuff to Home Depot).

 

[flyhigh123]

i've been runnning my ats for about 2-3 years now, however i've always been using CFL lamps... are LED's better and more efficient now? Trying to find ways to increase coverage and growth.

 

[ca1ore]

Question about how to best 'preserve' my ATS screen while doing a tank changeover. I imagine the changeover will require the main pump to be off for 6 - 8 hours which I'd think would kill off the seeded screen? My thought was to use a powerhead to maintain flow through my sump and just dangle the screen in the water until I am ready to restore the main pump. Anyone have any better suggestions?

 

[Floyd R Turbo]

I have let my screen hang in my display tank for 2 weeks. if we're only talking a few hours, you could put it in a ziplock bag with enough water to keep it wet. Or just throw it in the DT