Here are several updates:
Milburnr on the SC site had this great pic of his flow:
Quick review of why scrubbers work:
1. The light is very near the screen, and is not blocked by anything.
2. The flow is very rapid, which transports more nutrients to and from the algae.
3. The flow (on a vertical waterfall) is very thin, which breaks up boundary layer,
and which lets the most light through.
4. 7-day cleanings keeps the bottom layers of algae from being shaded and dying.
5. Using FW to clean, kills the pods that normally destroy the algae.
Seeding a new screen is no longer recommended, because (1) you get good growth in a week anyway, and (2) the seeding just washes off and adds nutrients to the water.
Barbianj on the RS site made a great high-power CFL setup:
Long vacations: Some people want to use a scrubber, but are gone two or three weeks at a time. Here are the options: The easiest is to do nothing. In this case, after three weeks, the underlying layers of algae will have died. When you return, the water may be cloudy and colored, and the nitrate and phosphate may be increased, but after a screen cleaning and some carbon, it will be back to normal in a few days. This option is ok if you leave only once or twice a year. Nothing should be harmed, however. The next option is to remove the screen. For very long trips, and for cases where you have lots of LR and DSB, this might be best. Of course your tank may develop nuisance algae during the trip because of lack of filtering, and you'll have to start the screen from scratch when you return.
RonRon on the RP site built one with just a tupperware box:
Here's another option to attach your screen: Curtain rings...
