New Scrubber Sizing Guideline (Sept 2011)
Scrubbers will now be 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)
1/2 frozen cube per day (1-sided screen)
10 pinches of flake food per day (2-sided screen)
5 pinches of flake food per day (1-sided screen)
10 square inches (50 sq cm) of nori per day (2-sided screen)
5 square inches (50 sq cm) of nori per day (1-sided screen)
0.1 dry ounce (2.8 grams) of pellet food per day (2-sided screen)
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.
HORIZONTAL screens: Multiply the screen size by 4, and the wattage by 1.5
Flow is 24 hours, and is at least 35 gph per inch of width of screen [60 lph per cm], EVEN IF one sided or horizontal.
Very rough screen made of roughed-up-like-a-cactus plastic canvas.
Clean algae off of screen every 7 to 14 days, so that you can see the white screen material.