Am I doing this right? -- Cyano on screen

[mmfrock]

Hi everyone,

I am new to this forum and new to algae scrubbers in general. I need a little advice. I have had my algae scrubber built and running for about 3 weeks now. I have done 3 or 4 cleanings. My scrubber is always full of cyano/light brown algae. I have definately seen improvements in my display tank as it used to have all the cyano and now the cyano is mostly all on the scrubber.

I know that eventually the goal is to get my scrubber green, however i am not sure why that's not happening. Here's my setup:

Pretty good amount of flow from gravity from the overflow i built
2 (26 watts each) bulbs on for about 16 hours

The first tank picture is before the algae scrubber and the second display tank picture was taken about 2 weeks in. The cyano has even improved since then in the DT.

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[SantaMonica]

Welcome to the site.

The main thing from the pics is fairly straight forward... the screen is way to big for the lights, and, the flow is cut off. Resize the screen by cutting it vertically, and tape up the remaining slot. Use this size...

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

An example VERTICAL 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 watts (not equivalent) of fluorescent light for 18 hours a day. If all 12 watts are on one side, it is a 1-sided screen. If 6 watts are on each side, it is a 2-sided screen, but the total is still 12 watts for 18 hours a day. This screen size and wattage 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)

High-wattage technique: Double the wattage, and cut the hours in half (to 9 per day). This will get brown screens to grow green much faster. Thus the example above would be 12 watts on each side, for a total of 24 watts, but for only 9 hours per day. If growth starts to turn YELLOW, then increase the flow, or add iron, or reduce the number of hours. And since the bulbs are operating for 9 hours instead of 18, they will last 6 months instead of 3 months.

Clean algae off of screen every 7 to 14 days, so that you can see the white screen material.

[mmfrock]

Wow, way to throw a lot of math at me! I am not a math thinker! I'll try to get this though...so you are saying to cut my screen size in half length wise. I can't really make my screen much shorter though b/c then it wouldnt be in/touching the water. And I am using 26 watts, so you're saying decrease the wattage and the amount of time the lights are on? And how can i tape up the remaining slot...what kindof tape resists water?

[mmfrock]

My screen is currently 6x9 w 2 (26watt each) bulbs. I had 2 (13watts each CFL) bulbs on it...should i put those bulbs back in and make the screen smaller?

[SantaMonica]

6 inches wide is good. 23 watts on each side is good. Get CFL spotlights and point them to the middle of the screen. 18 hours. New bulbs.

[mmfrock]

My 26 watts are CFL bulbs.

[SantaMonica]

Ok then just fix the flow so the whole screen is covered. Growth will fill in in 14 days.

[mmfrock]

So I cut my screen to be smaller, but it's now a "y" shape rather than a rectangle, becuase i cannot just chop off the bottom or else it won't touch the water and i cannot make the hanging apparatus any lower at this point. I still have cyano all over the screen so today i just cleaned off half of it instead of all of it. I also have been able to increse the flow a little by cleaning the slit in the pipe and not attached the screen so tightly. Do you think these things will make it turn green? I do see tiny dots of green in the bottom of the overflow tank but not on the screen yet. Also, should i lower the bulb hours?

[kerry]

I am not sure if I am making a mistake but I have one that does not touch the water.

[SantaMonica]

It's all about concentrating the growth in a small area with bright light. We will see; let it go 14 days.