Santa Monica DROP-10 UAS® Bubble Upflow Algae Scrubber

The DROP-10 needed to be the most scrubber surface area in the most compact space that could fit into large sumps but still leave room for other equipment. It's larger than even our current largest model SURF8. And it can never overflow since it's always underwater. We were the first to use 1" drain pipes on waterfall scrubbers in 2008, and we know they overflow easily. So the DROP-10 has NONE..

It's totally submersible. Or it can be put into as little as 6 inches of water, but filtering is reduced because some of the growth surface will be out of the water.

It needed a one-handed pull-out growth tray, because something this big would not fit into most sinks. So it's basically two scrubbers units... the inside growth tray and the outside illumination shell. Since it is not a waterfall, there is no growth that will fall to the bottom and need cleaning/scraping out, which is very difficult for most waterfalls because you have do disconnect plumbing first.

The lights needed to be easily replaceable, as well of course high power (1000 PAR each), and also submersible. So the design uses the well tested GEM5 lights in the 660nm deep red growth color (not white or pink), with snap-in light holders; and it routes the wires through a light-blocker. The lights shine directly (perpendicular) to the growth surface; not from above the surface which would be very ineffective.

To keep all the light in, the entire structure is black, but to maximize the light inside, the inside surfaces are covered with white. The growth surface is the very well tested Green Grabber growth surface with epoxy, heavy silica rock, and 2-sided growth attachment strings that reach out into the middle areas; not 1-sided smooth plastic material that only gets light on one side and can can barely hold on to anything (and will crack within a year).

The bubbling system was a challenge because the bubbler could not be attached to the tray or else you could not remove it with one hand. So it has patent pending bubble director funnels that allow you to lift out the growth tray without turning off or disconnecting anything, but still directs the bubbles to travel upwards to rub the growth surface. This rubbing removes the laminar layer of water around the algae so that the algae grow (absorb nutrients) faster than a waterfall.

The water circulation, which is powered by the bubbles, had to pull water in from under the growth tray in order to feed the water to the bubble director funnels, and it does this through 1/4" (6mm) circulation holes at the bottom, which are small enough to keep light in and keep livestock out. Then as water and bubbles flow upwards, the air needed to be separated from the water at the top of the growth tray, and this is done with a patent pending air containment compartment at the top, with strainers to keep algae and light from getting out; the water then circulates back around and exits the side circulation holes, which also block light.

Most of the panels are 3/16" thick PETG plastic panels, with the top panel being 1/4", and the bubble director panel being 1/2". 

The recommended air pump is the smaller 25 watt version here, which connects directly to the included silicone tubing:

14" (35cm) long 

5 1/2" (14cm) wide 

9" (23cm) tall (add extra 2" for handle)