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HOG3x Hang-On-Glass UAS Upflow Algae Scrubber with Green-Grabber surface and Xtra LEDs - 3 cubes feeding per day


Eliminate water changes. Remove nuisance algae, nitrate and phosphate. Cultivate seaweed for feeding!!!


HOG3x dimensions: Each cover is 6 5/8" wide x 8 3/4" high x 1 1/2" thick  (16.6cm wide x 21.9cm high x 3.75cm thick).


Operates on both 120 and 240V.


***Can ONLY be shipped in USA.***


No dangerous metal 240/120 volt lights.


Welcome to algae scrubbers. We are the only source for patented upflow scrubbers: U.S. Patent 9,115,008 and 9,708,207. All the oceans, reefs, lakes and rivers are naturally filtered only by algae, and all the organic particles remain in the water to feed the creatures. Reduce your glass cleaning and water changes, and create an environment for living micro-animals to grow inside the scrubber. No more dosing or possible overdosing. No more refilling. No more pale corals from low nutrients, and no more sick animals from high nutrients. Far more powerful than chaeto or refugiums, and does not remove the food particles. And you can use the algae as food!


Get the no-overflow advantage of an upflow scrubber: since it is ALL underwater, it can't overflow onto your floor. And now, all six of the magnets that go in the water are protected by a hard plastic cover inside of the black silicone; this prevents any scrapes or rust if you happen to accidentally let the magnets snap together. 


This HOG3x is a higher power 9-LED version of the original HOG3 which has 6 LEDs. This HOG3x also has two power supplies; one for a low-power 3-LED mode for startup when the growth surfaces are pure white, or for very new aquariums when there are not many nutrients in the water; and the second one to be added-in once growth darkens up the white surfaces.


This HOG3x, just like the original HOG3, offers much larger algae-attachment space to hold more growth between cleanings compared to the HOG.5, HOG1 or HOG1x, and is 2-sided instead of 1-sided because of the strings, compared to the HOG1.3 and HOG2 which have no strings. Thus this HOG3x is ideal for sumps of larger systems, because sumps rarely have thicknesses larger than 1/2" (13mm).


This HOG3x scrubber has 36 square inches (225 square cm) of two-sided algal growth surface textures and strings, which once growing is designed to absorb the nutrients from this much feeding per day: 


3 Frozen cubes, or

30 Pinches of flake, or

30 Square inches (180 square cm) of nori, or

8.4 grams of pellets


The number of gallons or liters of water in your tank or sump does not matter. If you feed more than the above amounts you can get multiple HOG3x units; multiple units are preferred over one larger unit because you can clean one unit per week, and because you'll always have one unit filtering while the other one starts growing again after a cleaning. Multiple units are also good for backup. The magnets attach the outside cover to the inside cover through the aquarium wall, and can be used on glass or acrylic 1/4 inch (6 mm) to 1/2 inch (13 mm). 


Compared to the HOG1.3 and HOG2 which look the same in size, the HOG3x is meant for situations which have nutrient or algae problems, even in cases where the rocks in the display are covered in thick green hair algae. Algae-covered rocks are the most difficult situations to fix because the photosynthesis of that algae on the rocks is consuming nutrients from the water (often it measures zero), making it harder for the HOG filter to get the nutrients. To combat this you need stronger photosynthesis in your HOG scrubber, and that is what the HOG3x is designed for. In particular, compared to the original HOG3, the extra LEDs of the HOG3x provide the highest photosynthesis yet in this size scrubber.


The large inside space of the HOG3x growth compartment allows for lots of build up of algae, but most importantly the 9-LED light provides the strongest photosynthesis of all the HOGs, giving it the best chance of out-competing the scrubber on your rocks and also cutting through the phosphate in the water as high as 0.5 ppm


The strings (ribbons) in the growth compartment of the HOG3x are the same strings that are in the SURF2, SURF2x, SURF4 and SURF8, and are the heart of the ability of the scrubber to be able to use all the space for initial growth. The strings on the HOG3x (like the original HOG3) allow this middle open area to start growing immediately, and do so using 2-sided growth (strings are 2-sided in growth) instead of the 1-sided growth of the textures alone. Thus the compartment fills much faster with growth, and this faster growth causes stronger photosynthesis (filtering).


The Green-Grabber (tm) algal growth surface is so rough and prickly that it might be the roughest thing you've ever felt. A cactus might be sharper, but that's about it. Rough surfaces are critical for allowing algae to attach and grow and thus provide strong absorption of nutrients. The rock-hard protrusions stick straight out 1 to 3 mm. Old style algae scrubber screens are made from "slippery" plastic canvas that is used for sewing and knitting; algae takes a long time to attach to it. Green-Grabber (tm) growth surfaces are not plastic at all; instead they are rock hard and have jagged rough edges and points (don't let children play with them).


This is a hand-built Hang-On-Glass® (HOG) Upflow Algae Scrubber® (UAS) with strings and a Green-Grabber growth surface, for glass or acrylic 1/4 inch (6 mm) to 1/2 inch (13 mm) thick.


No electrical parts go inside the aquarium; only air. 


Comes with 3 ft (90 cm) of vinyl airline, but requires an air pump that can pump at least 2.0 liters per minute (.07 cfm), preferably more. A pump that says it can handle 2 or more airstones/outlets, or a pump with 2 tubing attachments instead of one, will be needed. You can have as much air as you like, however; 10 lpm pumps are no problem (although it will be louder).


Comes with 9 red (660 nm) 3-watt LEDs, which are attached to a heat sink inside the cover; the cover does get warm. The LEDs will give the aquarium or sump a slight red color at night when the aquarium lights are off. You will need to get a timer so you can run the LEDs for up to 22 hours per day (not 24). A single timer to handle both power supplies is fine. The LEDs never needs replacing. 


The HOG3x growth compartment will need to be cleaned every 7 to 14 days, by removing the inside cover, disconnecting the airline, and taking the inside cover to the sink so you can brush the algae off of the growth surface and the bubbler with a toothbrush, and also off of the strings. Sometimes though you can just reach in and grab the growth, especially in saltwater.


Visit the Santa Monica Filtration Website for the full description: