Algae Scrubber Advanced
- Thread starter maglofster
- Start date
Brummie
Member
Excellent, thank you!
superdragon
Member
with a Upflow scrubber, is there any reason why it has to have a air stone and bubbles or can it be done with a pump circulating water over the screen?
What I'm asking is are the bubbles essential for the upflow scrubber to work
What I'm asking is are the bubbles essential for the upflow scrubber to work
SantaMonica
Well-known member
superdragon
Member
Good to know. Is there a typo on the picture? Should it say microalgae vs. macro.
jedimasterben
LED world domination!
Nope. You can get explosive growth with or without air, just need good water movement.
Hair and turf algaes are macro, not micro.
superdragon
Member
That's what I was thinking because hair algae grows like crazy in tanks without bubbles that have high flow and nutrients.
Thanks on the macro/micro clarification.
Actually you get the best nutrient exchange, thus greatest growth, with very turbulent water and lots of air, as in a shore environment between the low and high tide lines. Adday did the research years ago.
It has to do with breaking down the boundry layer of water that surrounds submerged algae.
I'm not sure that an airstone pushing bubbles across an algae bed qualifies though. I'm also not convinced that we need the absolute highest rate of growth out of algae to take advantage of a scrubber.
Floyd R Turbo
Either busy or sleeping
You are correct, in reality you only need the rate & amount of growth that your system requires in order to keep nutrients in check.
In some systems, this might mean you need the highest rate of growth per unit of growth substrate area as possible. For instance, a high bioload system with limited space for a scrubber
In other systems, you might not need optimal growth. For instance, a medium bioload system with room for a very large (oversized) scrubber. In such an instance, the growth would not need to be "optimal" or "maximum" on a per-square-inch basis, but on an overall basis, the growth is enough to keep things in check.
To a certain extent, this is why it is not difficult to build a scrubber that is not nearly "perfect" and still get very useful results.
herring_fish
Crazy Designer
Increasing inches of properly lighted screen, increasing flow rates and or increasing turbulence are the three pillars of increasing algal growth rates.
I think anybody who has read Dr. Adeys book or look at lots of studies on the "œInterWebs" would agree with Fredfish's notation showing the evidence is clear that direct water contact to algal strands is the optimal way to create gas, mineral and nutrient exchange which fosters optimal growth.
CO2 injection into the water has been studied many times but they rely on dissolving the gas into the water, not direct gas to algal strand contact. Even then, the increase was not that great. Injecting air bubbles is good for creating turbulence but not for an alternating wet, dry reaction.
Algae grows best in the tidal zone below the constantly submerged line not the constantly wet line. This is in spite of an increased chance of predation. Actually, fastest growth is a response to predation but that is another subject.
Floyd is also correct that, while studies show that water turbulence increases growth because in helps brake down the boundary layer, getting the absolute highest efficiency per square inch of lighted surface may not be best for your system.
The bubbles in Upflow scrubbers do increase turbulence that is better than some not as good as some others. The bubbles produce flow that is often at a gentle rate so it is better than some but not as good as others. "¦but (if anything) undissolved bubbles reduce water to strand contact time so let's not mix bubble turbulence with air absorption or algae respiration.
I think anybody who has read Dr. Adeys book or look at lots of studies on the "œInterWebs" would agree with Fredfish's notation showing the evidence is clear that direct water contact to algal strands is the optimal way to create gas, mineral and nutrient exchange which fosters optimal growth.
CO2 injection into the water has been studied many times but they rely on dissolving the gas into the water, not direct gas to algal strand contact. Even then, the increase was not that great. Injecting air bubbles is good for creating turbulence but not for an alternating wet, dry reaction.
Algae grows best in the tidal zone below the constantly submerged line not the constantly wet line. This is in spite of an increased chance of predation. Actually, fastest growth is a response to predation but that is another subject.
Floyd is also correct that, while studies show that water turbulence increases growth because in helps brake down the boundary layer, getting the absolute highest efficiency per square inch of lighted surface may not be best for your system.
The bubbles in Upflow scrubbers do increase turbulence that is better than some not as good as some others. The bubbles produce flow that is often at a gentle rate so it is better than some but not as good as others. "¦but (if anything) undissolved bubbles reduce water to strand contact time so let's not mix bubble turbulence with air absorption or algae respiration.
ATS in CSD?
ATS in CSD?
Hello to all. My first post (actually not really - I have posted some years ago but had login issues so started a new account). Maybe a little embarrassed and now humbled by the by the brashness exhibited in a few past posts. So thanks for the fresh start.
Some background first. I am roughing out a new build that will have a sump with LR, possibly a DSB. A quality external pump will pump water up 7 ft to a 3 part tank - a 20g mud refugium on the front and two 2g carlson surge devices at the back. The CSD's will each outlet down & through the back wall of a 25G cube DT below. The cube will overflow into another external CSD that will outlet into the LR compartment of the sump. I am looking to create a series of tanks, each properly dedicated to a specific reef biosphere function and do this as simply as possible.
The build will be functional in design first. Its a short term build that has to house the livestock from my first tank that desperately needs a rebuild to correct all the newbie mistakes and evolutions of the hobby in the last 6 years. (55g wDSB & LR, 30g sump, 15g RDSB & a 20g remote tank w LR, ATS and skimmer. DIY LEDs, Kalk stirrer, ATS & heat x-changer). Right out of the gate the 1st tank had a horrible stringy algae bloom that matted all the rock work and really, the tank has only survived from then on. Its quit or start over time. Decided I still find it an incredible richness to have a bit of the ocean in my house and will I give er another go.
The ATS forum relevant question is this - Would an ATS built into the CSD have a possibility of working out? Would the fill/empty cycles cycles be an acceptable substitute for pump induced flow? I have seen the idea of surge tanks progress through the pages of this forum (read it all - its great!).
In no small part, being able to tap into this wealth of knowledge and experience shared here has given me the confidence i need to press on. Thanks in advance to all.
ATS in CSD?
Hello to all. My first post (actually not really - I have posted some years ago but had login issues so started a new account). Maybe a little embarrassed and now humbled by the by the brashness exhibited in a few past posts. So thanks for the fresh start.
Some background first. I am roughing out a new build that will have a sump with LR, possibly a DSB. A quality external pump will pump water up 7 ft to a 3 part tank - a 20g mud refugium on the front and two 2g carlson surge devices at the back. The CSD's will each outlet down & through the back wall of a 25G cube DT below. The cube will overflow into another external CSD that will outlet into the LR compartment of the sump. I am looking to create a series of tanks, each properly dedicated to a specific reef biosphere function and do this as simply as possible.
The build will be functional in design first. Its a short term build that has to house the livestock from my first tank that desperately needs a rebuild to correct all the newbie mistakes and evolutions of the hobby in the last 6 years. (55g wDSB & LR, 30g sump, 15g RDSB & a 20g remote tank w LR, ATS and skimmer. DIY LEDs, Kalk stirrer, ATS & heat x-changer). Right out of the gate the 1st tank had a horrible stringy algae bloom that matted all the rock work and really, the tank has only survived from then on. Its quit or start over time. Decided I still find it an incredible richness to have a bit of the ocean in my house and will I give er another go.
The ATS forum relevant question is this - Would an ATS built into the CSD have a possibility of working out? Would the fill/empty cycles cycles be an acceptable substitute for pump induced flow? I have seen the idea of surge tanks progress through the pages of this forum (read it all - its great!).
In no small part, being able to tap into this wealth of knowledge and experience shared here has given me the confidence i need to press on. Thanks in advance to all.
Floyd R Turbo
Either busy or sleeping
If anything you would want the scrubber to be on the receiving end of the surge, not within the CSD box itself. It is during rapid water motion that filtration occurs because this is when the boundary layer is broken. You don't get this when you have a box with screen hanging in it that just fills up slowly and then empties out suddenly.
But if you have a dual CSD surging into a tank that overflows into a CSD, then basically you have the two CSDs filling the third kind of "bang-bang" and in the 3rd CSD you might get a rapid fill followed by a rapid drain, with the next rapid fill right behind it. If this is what you are thinking (the first 2 CSDs have sort of "opposite timing") then the scrubber in the 3rd might actually work.
Pretty complicated...but it could work.
But if you have a dual CSD surging into a tank that overflows into a CSD, then basically you have the two CSDs filling the third kind of "bang-bang" and in the 3rd CSD you might get a rapid fill followed by a rapid drain, with the next rapid fill right behind it. If this is what you are thinking (the first 2 CSDs have sort of "opposite timing") then the scrubber in the 3rd might actually work.
Pretty complicated...but it could work.
SantaMonica
Well-known member
No, a simple rising and falling of water in a container will not do anything. However you could have the surge spill over onto the scrubber, which would work. Of course, it would work this way with no surge, too.
Alternate ATS options
Alternate ATS options
I hope that i end up with an oxymoron. Complicated in the planning and construction but simple, unique and mesmerising when done.
. Your idea is certainly in the mix. Funny thing, i was already contemplating it because i had seen it in an earlier post - but it was right after a dump bucket post by asa...herring [6348] so it didn't register that it was your post just down the page that put the idea out there. Thanks I could add a CSD between the DT and the sump to serve such a unit . mmmm.
Could you help me distill a couple of other ideas? The rendering below shows the top display refugium tank with the two CSD units in the back that provide the motion for the cube below. One of the ideas in play is a horizontal single sided ATS - depicted as the green shelf between the CSD chambers. Would the optimum flow needed by an ATS like this [9x9"] be more than the optimum turnover for a 20g mud fuge [3 to 4x]? Could a dump bucket be scaled down small enough to provide a unique fuge flow? Might the ATS growth easily throw off the balance of such a small dump like this?
your input is valued.
[/IMG]
Alternate ATS options
I hope that i end up with an oxymoron. Complicated in the planning and construction but simple, unique and mesmerising when done.
. Your idea is certainly in the mix. Funny thing, i was already contemplating it because i had seen it in an earlier post - but it was right after a dump bucket post by asa...herring [6348] so it didn't register that it was your post just down the page that put the idea out there. Thanks I could add a CSD between the DT and the sump to serve such a unit . mmmm.Could you help me distill a couple of other ideas? The rendering below shows the top display refugium tank with the two CSD units in the back that provide the motion for the cube below. One of the ideas in play is a horizontal single sided ATS - depicted as the green shelf between the CSD chambers. Would the optimum flow needed by an ATS like this [9x9"] be more than the optimum turnover for a 20g mud fuge [3 to 4x]? Could a dump bucket be scaled down small enough to provide a unique fuge flow? Might the ATS growth easily throw off the balance of such a small dump like this?
your input is valued.
Floyd R Turbo
Either busy or sleeping
2ccs what happened to your post here and on the basics thread?
Floyd R Turbo
Either busy or sleeping
2ccs I thought what you were describing was one CSD cascading into the other, I guess I misinterpreted your post
Is there a reason you would not want to do a waterfall scrubber?
Is there a reason you would not want to do a waterfall scrubber?
Sorry, a bit scattered. Ist idea to be soundly eliminated was having an ATS inside a slowly filling CSD. Your cascading CSD suggestion is certainly in the mx. It could be incorporated using a 3rd CSD receiving the flow post DT tank and dumping into an ATS located in the sump. Certainly has merit. A waterfall scrubber would need its own light (maybe a good thing) and would be located in the base of the stand (i really dislike working on my knees in tight places). Not really a compelling reason not to go with one yet.....
I am also contemplating the idea of a small dump bucket style ATS located as depicted by the green shelf. I could share the refugium LED with this ATS with this layout. I am pondering if a gentle dump into the fuge may actually be a good flow for the fuge.
I am also contemplating the idea of a small dump bucket style ATS located as depicted by the green shelf. I could share the refugium LED with this ATS with this layout. I am pondering if a gentle dump into the fuge may actually be a good flow for the fuge.
After reading Adey's book back when it first was published, I dutifully went off and built a dump bucket style scrubber. Worked OK, though seemed to grow brittle stars better than turf alage. Eventually I abandoned it. More recently I built a waterfall scrubber based on the advice contained in this and other threads here on RC. No comparison, the waterfall is better in all respects (and still grows brittles )
)SantaMonica
Well-known member
Yes that's sort of how I looked at the dump buckets in 2008, "there must be an easier way to move water across a screen", and that's how I came up with the waterfall (let gravity do the work).
