Building Your Own Algal Turf Scrubber (ATS)

Ponraj A · Apr 23, 2019

Superb and thanks for providing your knowledge.

hyla84 · Apr 23, 2019

ca1ore said:
Haha, I think you'll get a whole lot of different views on that. Here's mine …… I personally have found that the accepted guidelines are a bit too low, in other words I need more surface area per cube equivalent that the recommendation. I feed about 12 cube equivalents daily and the current screen is 480 square inches (counting both sides) with all screen area growing algae; so that's 40 square inches per cube. Another way to 'size' is to use 1 square inch double lit per gallon of water.

After reading your guide a I am planning to built one as well.
I have a 400 liters tank.
How big would it be the canvas for my thank?
So I can plan the dimensions of the entire box
Thanks [emoji16]

SantaMonica · Apr 26, 2019

Just found this threat. Glad my original waterfall design is helping out many people.

chicago · Apr 28, 2019

mine is back up and rocking... question.. i recently started scrapping off 1/2 at a time and alternating .. that way its at least full growth 50% of the time. I hang two sheets of screen..

SantaMonica · Apr 30, 2019

Yes the split-sheet has been working well for many years now, so keep doing that if it's easy for you.

hyla84 · May 1, 2019

SantaMonica said:
Yes the split-sheet has been working well for many years now, so keep doing that if it's easy for you.

Which measure the sheet would it be the best for a 400 lt tank?

SantaMonica · May 5, 2019

Scrubbers are sized according to feeding. Nutrients "in" (feeding) must equal nutrients "out" (scrubber growth), no matter how many gallons or liters you have. So...

An example VERTICAL upflow or waterfall screen size is 3 X 4 inches = 12 square inches of screen (7.5 X 10 cm = 75 sq cm) with a total of 12 real florescent watts (not equivalent watts) of light, or half that for LEDs, for 18 hours a day. If all 12 watts (6 watts LED) are on one side, it is a 1-sided screen. If the watts are divided on each side of the screen, it is a 2-sided screen. This should be able to handle the following amounts of daily feeding:

1 frozen cube per day (2-sided screen), or
1/2 frozen cube per day (1-sided screen), or
10 pinches of flake food per day (2-sided screen), or
5 pinches of flake food per day (1-sided screen), or
10 square inches (60 sq cm) of nori per day (2-sided screen), or
5 square inches (30 sq cm) of nori per day (1-sided screen), or
0.1 dry ounce (2.8 grams) of pellet food per day (2-sided screen), or
0.05 dry ounce (1.4 grams) of pellet food per day (1-sided screen)

Problem rocks: Each 50 pounds (2.2 kg) of nuisance algae covered rocks you have adds 1 cube a day.

Flow or air bubbles is always 24 hours; water flow is at least 35 gph per inch of width of screen [60 lph per cm], EVEN IF one sided or horizontal.

FLOATING SURFACE SCRUBBERS WITH STRINGS: Screen size is the size of the box (Length X Width), and is 2-sided because the strings grow in 3D.

Clean algae:

Every 7 to 14 days, or
When it's black, or
When it fills up, or
When algae lets go, or
When nutrients start to rise

Josh@ClearWaterScrubbers · May 7, 2019

SantaMonica said:
Scrubbers are sized according to feeding. Nutrients "in" (feeding) must equal nutrients "out" (scrubber growth), no matter how many gallons or liters you have. So...

An example VERTICAL upflow or waterfall screen size is 3 X 4 inches = 12 square inches of screen (7.5 X 10 cm = 75 sq cm) with a total of 12 real florescent watts (not equivalent watts) of light, or half that for LEDs, for 18 hours a day. If all 12 watts (6 watts LED) are on one side, it is a 1-sided screen. If the watts are divided on each side of the screen, it is a 2-sided screen. This should be able to handle the following amounts of daily feeding:

1 frozen cube per day (2-sided screen), or
1/2 frozen cube per day (1-sided screen), or
10 pinches of flake food per day (2-sided screen), or
5 pinches of flake food per day (1-sided screen), or
10 square inches (60 sq cm) of nori per day (2-sided screen), or
5 square inches (30 sq cm) of nori per day (1-sided screen), or
0.1 dry ounce (2.8 grams) of pellet food per day (2-sided screen), or
0.05 dry ounce (1.4 grams) of pellet food per day (1-sided screen)

Problem rocks: Each 50 pounds (2.2 kg) of nuisance algae covered rocks you have adds 1 cube a day.

Flow or air bubbles is always 24 hours; water flow is at least 35 gph per inch of width of screen [60 lph per cm], EVEN IF one sided or horizontal.

FLOATING SURFACE SCRUBBERS WITH STRINGS: Screen size is the size of the box (Length X Width), and is 2-sided because the strings grow in 3D.

Clean algae:

Every 7 to 14 days, or
When it's black, or
When it fills up, or
When algae lets go, or
When nutrients start to rise

That is false to size them by feeding. The same nutrients into a 65g do not equal the same nutrients into a 180g. Dilution drastically throws off your “feeding” equation. Especially when nitrates and phosphates are measured in ppm and that is the same way that algae consumes them. Also, most coral foods seem to break down much faster than any fish food. So while that was a good start, they need to be sized by aquarium size.

hyla84 · May 7, 2019

So every 100 liters how big should it be? Thanks

Scrubber_steve · May 7, 2019

Josh@ClearWaterScrubbers said:
That is false to size them by feeding. The same nutrients into a 65g do not equal the same nutrients into a 180g. Dilution drastically throws off your “feeding” equation. Especially when nitrates and phosphates are measured in ppm and that is the same way that algae consumes them. Also, most coral foods seem to break down much faster than any fish food. So while that was a good start, they need to be sized by aquarium size.

LOL. So you're suggest a 500g tank with one fish should use the same size scrubber as a 500g tank with 30 fish?
LOL, again

Josh@ClearWaterScrubbers · May 7, 2019

Scrubber_steve said:
LOL. So you're suggest a 500g tank with one fish should use the same size scrubber as a 500g tank with 30 fish?
LOL, again

What are you LOL’ing about? Please provide some data to back up your claims.

Nutrients in don’t equal nutrients out... do you expel the same amount of waste that you take in? Neither do fish! They use most of that as energy for life. Just like you or I. Also, please show me where one cube of food in a 65g equates to the same ppm of nutrients in a 500g as your example states.

While it does help to size on smaller tanks, what Santa Monica only builds for. It DOESN’T work for larger systems. just because it’s been out on the internet for a few years, doesn’t mean it’s the Bible when it comes to sizing the correct scrubber.

Scrubber_steve · May 7, 2019

Josh@ClearWaterScrubbers said:
What are you LOL’ing about? Please provide some data to back up your claims.

Nutrients in don’t equal nutrients out... do you expel the same amount of waste that you take in? Neither do fish! They use most of that as energy for life. Just like you or I. Also, please show me where one cube of food in a 65g equates to the same ppm of nutrients in a 500g as your example states.

While it does help to size on smaller tanks, what Santa Monica only builds for. It DOESN’T work for larger systems. just because it’s been out on the internet for a few years, doesn’t mean it’s the Bible when it comes to sizing the correct scrubber.

Josh; a scrubber doesn't care what the ppm of nutrients are in the water (unless its absolute zero), it simply uses whats available, to its maximum potential, during photosynthesis. Specifically, the nutrients removed during a given period, say 5 minutes, will be the same no matter the ppm level of nutrients in the water flowing over the screen. What one needs is a scrubber with the correct screen size & illumination intensity & photo period to utilise those nutrients at a rate that prevents the nutrients rising to unacceptable levels. So the amount of nutrients in the water, & the rate of flow of water carrying those nutrients through the scrubber is what determines the baseline nutrient level.

The nutrient level created by feeding x amount of food to a small tank will show up as a higher ppm than the same amount of food feed to a large tank because of the difference in the volume of water between the two. But when using the same size scrubber on both tanks to reduce the nutrient level, using the same flow rate per hour through the scrubber, the result in nutrient reduction will be the same because the tank turnover per hour through the scrubber on the smaller tank will be greater than the tank turnover rate per hour through the same scrubber on the larger tank.

Simply, if you have the correct screen size that deals with the export of inorganic nutrients efficiently, if you triple the amount of food fed to the tank the inorganic nutrient level will slowly rise over time, unless a larger screen, with appropriate lighting is used.

Reef-junky · May 8, 2019

Mine is much more compact.

jorahx · May 8, 2019

Reef-junky said:
Mine is much more compact.

Is it loud? Splashing?

SantaMonica · May 8, 2019

That is compact. Makes the top pipe look huge.

Reef-junky · May 8, 2019

jorahx said:
Is it loud? Splashing?

No the bottom pipe sits just under water. The screen touches the bottom bulkhead because of the small amount of water that sits in the bottom you don’t get a waterfall effect.