Algae Scrubber Basics

[Floyd R Turbo]

Yes, but the water doesn't flow around the world once per day

If one was *really* worried about nutrients staying low 24/7, and it would have to be a very sensitive system to *really* need such a thing, then you would want to opt for a dual-scrubber system, where one was lit while the other was off. Either way, the algae needs dark time. You could even do a system with 2 screens in one slot tube with a gap between them and light blocking to separate the halves, and separate lighting, just as long as one side had all the light blocked.

 

[redneckgearhead]

I guess I am just lucky. I haven't noticed an increase in my electric bills. I'm not sure how overloaded your tank would have to be to see a spike in nutrients in the short "night" time period. Maybe we could get the scrubber only guys to test that theory.

 

[Amphiprion]

Amp, several have tried white LEDs and red alone blows them away. I would highly advise against using any white spectrum LEDs. Check the advanced thread for much discussion on this issue.

Sorry, I meant NW and red. I still think that some slightly broader spectra may be beneficial. Should end up looking around 2700K.

 

[Floyd R Turbo]

Talk to some hydroponics guys. They will tell you different. My guy has a degree and 15 years experience. For flowering plants, yes. For what we need it for, no.

Redneck, when I moved the contents of the system I maintain (twice in one week) the scrubber was offline for a week or more. I just had the screens hanging in the DT in the general direction downstream of a power head. No algae grew of significance, just kept the screen from dying. During that time, N went from zero to somewhere between 2 and 5, maybe it got to 10, I don't recall, and Phosphate went up to about 0.63 IIRC. 2 days after the scrubber was back online, N=0 P<0.1.

Keep in mind, I took everything out of one tank and put it in another tank, changed about 40% of the water, then did it all again 3 days later, and changed about 30% of the water, then let it sit for a week and that is when the N and P got to where I mention above. All that kicking stuff around and commotion, not to mention drastically shifting the flow patterns of everything in the tank, killing sponges from air exposure, etc etc etc.

Therefore I have a very difficult time recommending to anyone that they need dual-scrubbers.

 

[der_wille_zur_macht]

If one was *really* worried about nutrients staying low 24/7

I am asking this out of partial ignorance, but do we actually know the relationship between nutrient uptake and photoperiod?

Clearly photosynthesis is only happening when algae are lit, but it was my understanding that much of the actual "growth" (cell division) actually happens during lights out. Regardless, does anyone have any hard data correlating nutrient uptake with photoperiod?

 

[Amphiprion]

I am asking this out of partial ignorance, but do we actually know the relationship between nutrient uptake and photoperiod?

Clearly photosynthesis is only happening when algae are lit, but it was my understanding that much of the actual "growth" (cell division) actually happens during lights out. Regardless, does anyone have any hard data correlating nutrient uptake with photoperiod?

There's a lot out there on it--in both vascular plants and green algae. Assimilation is dependent on growth, which is dependent on photosynthesis. Uptake occurs all the time, but it is largely utilized during photosynthetic hours.

 

[BluScrnOdeth]

Yes, but the water doesn't flow around the world once per day

lol, so true

 

[Amphiprion]

Talk to some hydroponics guys. They will tell you different. My guy has a degree and 15 years experience. For flowering plants, yes. For what we need it for, no.

Are you primarily talking about green turf types? Has anyone done comparisons on other turf types like browns, which are primarily what I had on my screens.

 

[Floyd R Turbo]

I'm not really talking turf at all, because true turf algae grows rather slowly and does not filter very efficiently when compared to green hair algae. That's why we all stopped calling them Algal Turf Scrubbers and started calling them Algae Scrubbers, because that is technically correct. True "turf" scrubbers are generally the older horizontal dump/surge style ones.

If you don't have green hair on your screen, then you probably need an adjustment made to some factor, probably increasing the lighting intensity. You want GHA because it does the best job filtering.

 

[parrotchute]

Yes, but the water doesn't flow around the world once per day

If one was *really* worried about nutrients staying low 24/7, and it would have to be a very sensitive system to *really* need such a thing, then you would want to opt for a dual-scrubber system, where one was lit while the other was off. Either way, the algae needs dark time. You could even do a system with 2 screens in one slot tube with a gap between them and light blocking to separate the halves, and separate lighting, just as long as one side had all the light blocked.

I'm SORT of running that on my new scrubber - not experienced enough with scrubbers yet to draw a conclusion on the results, but I have the left/right sides on different timers, 4pm-10am + 3pm - 9am. I figure it gives me a little more "coverage"..

 

[parrotchute]

I'm not really talking turf at all, because true turf algae grows rather slowly and does not filter very efficiently when compared to green hair algae. That's why we all stopped calling them Algal Turf Scrubbers and started calling them Algae Scrubbers, because that is technically correct. True "turf" scrubbers are generally the older horizontal dump/surge style ones.

If you don't have green hair on your screen, then you probably need an adjustment made to some factor, probably increasing the lighting intensity. You want GHA because it does the best job filtering.

Floyd, how long should one expect to be running the scrubber before seeing GHA?

I know there are a lot of factors to include nutrient level, age of tank, age of scrubber, but I'm just wondering how long to wait before I conclude something needs adjustment.

 

[Thras]

Ok I did live plants I'm my fw set up and if I remember correctly photosynthesis took place in the day using up the co2 in the water and nutrients and storing them and putting o2 back in the water then at night it releases co2 and uses o2 using the stored nutrients and grows but this is plants in fresh water so it could be different with algae but with the water flowing in a sheet like it is you wouldn't have to worry about o2 getting low because it dissipates the co2 and o2 that's why people with plants and co2 bottles to feed them don't like bio wheels because it takes the co2 out and brings in more o2 and they run air pumps at night so there fish don't gasp for air

Sorry I think I read a few pages back on some stuff with light and dark and nutrient take up

Feel free to correct me if I'm wrong

 

[Floyd R Turbo]

I dug up these old pics of when I first started the scrubber:

10/16/10 - week 1

10/21/10 - week 2

10/29/10 - week 3

11/01/10 - week 4

11/09/10 - week 5

11/16/10 - week 6

 

[srusso]

Floyd, how long should one expect to be running the scrubber before seeing GHA?

I know there are a lot of factors to include nutrient level, age of tank, age of scrubber, but I'm just wondering how long to wait before I conclude something needs adjustment.

A properly built scrubber should have mostly green growth in 4 - 6 weeks.

 

[redneckgearhead]

Hey Floyd, I just had an idea wanted to run it by you see what ya thought. I am looking into making some fish additions to my tank. I do not have my QT tank cycled. I was thinking I could cut strips of screens and put them in the bottom of my AS box allowing them to get covered in HA and then once I set up my QT I would tie one of those strips to the filter box and have a light over it. This should help with the ammonia levels correct? I know I wouldn't be able to medicate with it in there but as long as the fish shows no signs I usually just hypo. Watcha think?

 

[parrotchute]

Thanks Floyd/Srusso! I'll continuing posting my results with the eshine LEDs. I also have a PAR meter on order, so I'll post both my scrubber/DT numbers to help the cause.

Floyd, are those pics WITH cleanings each week!? That's amazing, it looks heavy!

 

[Floyd R Turbo]

Yes, those are right before cleanings, each week scraping most of everything off.

Redneck, I would attach them with really small zip-ties to the screen rather then setting in the bottom of the box. Give it a good 2-4 weeks. The strips will probably grow enough so that you actually have to scrape it off or peel it away from the original screen. I don't know about your filter box and what it looks like, but if you're talking about an HOB and you're going to lay it so that it is on the return spillway, that might work for a very small bioload. Also you can take it out to medicate the tank, then once the medication is removed you can put it back on. Not sure how well it will work though, that's essentially a horizontal scrubber.

 

[redneckgearhead]

Thanks floyd, Ill give it a try and post the results.

 

[der_wille_zur_macht]

Does anyone see value in seeding a new screen on a more or less sterile tank?

My 360g has been running for about a month. ATS isn't exactly correct by most standards but it's pretty close. It's just growing brown slime.

My tank was put together with dead, dry sand and rock, fish, and corals. It's basically 100% devoid of typical "pests" and algae you get as hitchhikers in a typical tank. I'm wondering if I should be trying to get a snippet of a used screen to seed the tank with the typical algae species, because I'm seriously questioning if the tank has any of these species present at all.

 

[srusso]

Does anyone see value in seeding a new screen on a more or less sterile tank?

My 360g has been running for about a month. ATS isn't exactly correct by most standards but it's pretty close. It's just growing brown slime.

My tank was put together with dead, dry sand and rock, fish, and corals. It's basically 100% devoid of typical "pests" and algae you get as hitchhikers in a typical tank. I'm wondering if I should be trying to get a snippet of a used screen to seed the tank with the typical algae species, because I'm seriously questioning if the tank has any of these species present at all.

IMHO, its best to let it do its thing.