Algae Scrubber Basics

[Floyd R Turbo]

If you are not feeding much then you don't need much light, anything too much will photosaturate any growth that is occurring.

IMO you don't need to just reduce the light intensity, but also the photoperiod, and split it up as well.

Any time you have problems getting growth to start, or have problems with growth not going green, that means you are usually blasting it with way too much light.

The 18 hour rule is only (ONLY) for CFLs on waterfall scrubbers. The rule on LEDs is to start out with 9 hours/day maximum total (cumulative) photoperiod per day, and adjust up only after the screen/substrate is mature and increasing light period/intensity does not cause a decrease in growth.

So my suggestion for your DIY floating UAS is to reduce the total hours of on time to 6 hours/day, and make that three 2-hour photoperiods with at least 30 minutes between each. You could also do six 1 hour periods, etc. Shade cloth, yeah if you have one you could do that, or if you have the ability to reduce the current to say 500mA, do that. If you use the shade cloth I would still split up the photoperiod and you might be able to add another 2 hours (for 8 hours total).

But the 18 hours/day of full current red is the problem. And like Jedi said, if it's 630nm red, that's another problem - that is 3x stronger than 660nm red and will photosaturate a lot faster, especially with that proximity.

 

[SantaMonica]

dark brown/black and really goey

Lights are way to weak, compared to the amount of nutrients in the water.

 

[Floyd R Turbo]

With a 105 gallon tank and only 2 clowns, it's not high nutrients. The clear algae is a sign of photosaturation = too much light. I stand by my recommendation.

 

[Triggerfish]

setting the scrubber up has by far been the best thing i have done with my tanks. 20 fish in a 110 and trates remain at zero. no more coral deaths...

 

[Reef Junky]

Getting some thicker green stuff here at week 3. Still waiting for decline of the ha in dt.

 

[Floyd R Turbo]

Looking good so far, that's nice bright green growth

 

[Triggerfish]

been reading up on preferred SPS requirements. i have mostly frags and looking for growth over color right now/. so it looks like its recommended to have higher alk/ but with that the system will need to have a small level of detectable NO3.

so wondering if after the weekly cleaning i wait a day or so before running back up to allow some nutrients to build up for hte corals to utilize?

 

[Reef Junky]

Looking good so far, that's nice bright green growth

As bad as the outbreak is in the dt of ha I expect amazing growth on screen. After reactors going offline coupled by skimmer dying then rebuilding sump fuge room setup the dt suffered a major outbreak. I'm hoping this new setup will eradicate algae in dt without reactors and maintain future nutrient consumption etc. Only time will tell.

 

[Floyd R Turbo]

been reading up on preferred SPS requirements. i have mostly frags and looking for growth over color right now/. so it looks like its recommended to have higher alk/ but with that the system will need to have a small level of detectable NO3.

so wondering if after the weekly cleaning i wait a day or so before running back up to allow some nutrients to build up for hte corals to utilize?

As long as you are feeding, there will always be some level of nitrate in the water, it doesn't go completely away. Remember, people run ULN systems and SPS corals.

I have 2 systems with 0 nitrates and all corals grow nicely (that's stark yellow in API and usually a very very pale pink on Salifert when looking through the side, and sometimes that is even clear of pink tint)

 

[SantaMonica]

so wondering if after the weekly cleaning i wait a day or so before running back up to allow some nutrients to build up for hte corals to utilize?

Better to just feed more.

 

[Reef Junky]

third scrapping, three and a half weeks in. Finally pulling some good stuff.

 

[Floyd R Turbo]

I guess I didn't realize you were scraping every week. Let it grow longer - go 10 days then scrape. When running CFLs you have to use a bit of trial and error to determine how long is too long of a growth period, because CFLs give good broad even coverage but don't penetrate super-deep. But, you still should be able to let it grow longer than 7 days, and during the first month, you start out with thin layers of growth anyways so there's not much growth for light to have to penetrate through.

 

[Reef Junky]

Ok, will do. Thanks for the advice.

 

[Crispy001]

So I've been lurking through this thread for awhile and been slowly planning to try an ATS on my next tank. I plan to build it myself, and have been wondering if there's been much experimentation with submerged scrubbers like the upflow designs, but without airflow. I don't doubt that the gas exchange would help somewhat, but my initial suspicion is that its effects are small. I'm inclined to believe that a low flowrate of water and adequate lighting would be sufficient. Thoughts?

 

[jedimasterben]

So I've been lurking through this thread for awhile and been slowly planning to try an ATS on my next tank. I plan to build it myself, and have been wondering if there's been much experimentation with submerged scrubbers like the upflow designs, but without airflow. I don't doubt that the gas exchange would help somewhat, but my initial suspicion is that its effects are small. I'm inclined to believe that a low flowrate of water and adequate lighting would be sufficient. Thoughts?

My scrubber is submerged and I have no aeration beyond the overflow pushing some bubbles down, but it's not to the extent that I've seen other UAS, and I've got plenty of good growth (probably would be a lot better if I would feed consistently lol).

 

[herring_fish]

The original design was proposed as a way to minimize plankton damage as they go through the impellers of a standard pump. Bubbles were part of the design because they push the water past the plate or screen, not for gas exchange.

If you aren't using it for a dedicated plankton culture, then gas exchange is not so important. In a well designed algal turf scrubber, dissolved oxygen levels are near the saturation level so gas exchange is not important.

Several studies have been made, particularly for commercial operations and little improvement has been demonstrated. Direct injection of CO2 improves algal production but in most cases, it has not been enough of an improvement that the effort warrants the effort and expense. Direct CO2 injection can also have its drawbacks. Improving gas exchange is not really that important.

It's all about getting water to the individual algae strands. If that can be done, then exchange happens most efficiently with water to cell exchange.

 

[jedimasterben]

The original design was proposed as a way to minimize plankton damage as they go through the impellers of a standard pump. Bubbles were part of the design because they push the water past the plate or screen, not for gas exchange.

Most 'plankton' are not damaged as they get pushed through a pump's impeller, otherwise aquariums with things like refugia, etc that are detached from the display tank would essentially 'run out' of things like copepods, etc in the display.

 

[Floyd R Turbo]

The original design...

Which design are you referring to, Adey's?

 

[herring_fish]

Yes "¦there is much debate about whether there is a loss of 10% per pass of 25% or 1% but in a dedicated plankton culture, anything that you can do can be helpful.

Anyway, that was way the bubbles were used.

 

[herring_fish]

Which design are you referring to, Adey's?

No I looked. He used air lifts but no algae screens directly influenced by bubbles.

I think the first one was 11/04/2009 and was non-tramatic designed to promote plankton growth in a dedicated culture.