Mega Powerful Nitrate and Phosphate Remover - DIY!

1 watt per sq inch is for 18 hours. 2 watts per sq inch is for 9 hours. Always at least 35 gph per inch of screen.

96 total watts is both sides totalled up.
SM- Whats your take on elevated magnesium and ats? Many people have elevated their mag to rid algae. My mag level is approximately 1500ppm.
What to do if the flow across the screen isn't even? I'm getting dry spots and the flow at the end of the screen (furthest from the pump) is strongest. I just did my first cleaning and even tried to clean the slot out with a pair of scissors so that there aren't any upwards protruding pvc from the cut.
I'm planning a new 125 gallon tank with a 45 gallon sump that has a big refugium. Does this scrubber work better than a refugium? If so should I try to do this in the spot meant for the refugium, or have both? Thanks in advance for your opinions.
So if I have two overflow pipes going into my sump, I would divert one to flow over the scrubber (middle/refugium section), and the other would fall into the first section (skimmer area). The water gets pumped out of the third section at 1200 gph, so I guess the flow that would go to the scrubber would be 600 gph. I should make the scrubber 12"x12" since the tank is 120 gallons. Does this sound okay? Thanks so much for your advice.
I plan to be slightly understocked on fish, as I don't like the look of too many fish. Just a tang, an angel, two clowns, and maybe 5-6 smaller (like 2") fish. I guess I would feed one frozen cube a day? I'm still slightly confused as to how much food is best for a tank.
Probably two.

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.
Okay, let me make sure I understand you. If you say I should be feeding 2 cubes a day (or 1 cube and 10 pinches of flakes), I would take the example above and double the size and wattage. And it sounds like it's better to do the 2-sided screen, so I will try that. Am I okay with the flow and having it in the middle section? Will it be a problem to have one overflow going into the 1st section (skimmer section) and one overflow going into the middle section (with scrubber)?