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HOG1 Hang-On-Glass UAS Upflow Algae Scrubber with Green Grabber surface - 1 Cube feeding per day


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



HOG1 dimensions: Each cover is 5" wide x 6 5/8" high x 1" thick  (12.7cm wide x 16.8cm high x 2.5cm 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.


This HOG1 is the overall best choice if you don't know anything about algae scrubbers, and you don't know how thick your aquarium walls are, or how much filtering you need. It has over 24 square inches (150 square cm) of algal growth surface, which is designed to absorb the nutrients from this much feeding per day: 


1 Frozen cube, or

10 Pinches of flake, or

10 Square inches (62 square cm) of nori, or

2.8 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 HOG1 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 (6.25 mm) to 1/2 inch (12.5 mm). Not more. If your aquarium wall is 3/4" (19mm) or bigger, then put the HOG1 on your sump walls instead; it will work the same. Or get the HOG1.3 instead; it can attach to much thicker walls than the HOG1.


This HOG1 was the first algae scrubber with Green Grabber (tm) growth surfaces. Green Grabber surfaces are so rough and prickly that they 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. Older 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). Green Grabber surfaces are so good at grabbing algae and letting it grow that you may start seeing tiny growth spots within hours, instead of days. The white color of the Green Grabber surface reflects as much light as possible, getting almost the effectiveness of a 2-sided screen even though it really only has a light on one side of the surface.


The ability of the Green Grabber surface to hold on to thick algal growth helps greatly when you are cultivating algae/seaweed to feed back to your livestock. As the growth gets thicker and longer, the rapid bubbles will try to pull the algae off of the surface; the super rough Green Grabber surface will allow the algae to stay attached until you are ready to feed the algae/seaweed to your animals.


This is a hand-built Hang-On-Glass® (HOG) Upflow Algae Scrubber® (UAS) with a Green Grabber (tm) growth surface for glass or acrylic 1/4" (6.25mm) to 1/2" (12.5mm) thick. This is the typical thickness range for small and medium aquariums, and all sumps, however, you should measure yours to be sure.


If your tank uses thin 1/8" (3mm) glass such as many low-cost 10 gallon aquariums do, this filter is not recommended because the magnets are strong enough that they might crack the glass. You would be better off getting a lower cost HOG.5 filter HERE


No electrical parts go inside the aquarium; only air. And the air bubbler is already supplied (its sealed behind the growth surface), so you don't have to get an airstone. The bubbler is simply vinyl air hose that has been cut lengthwise, and with cross-cuts, to form little flexible segments that are both adjustable and open-able to allow for easy cleaning. This HOG1 will run on both 120V and 240V, and comes with a 10 ft (300 cm) power cord with a U.S. plug. If you require a different plug you can get an adapter at any local hardware or travel store, or online, or you can cut off the U.S. plug and install your own plug from a hardware store.


Comes with 3 ft (90 cm) of vinyl airline, but requires a small air pump. Most air pumps will work, but a 2-outlet air pump combined into 1-outlet (using a "T" or "Y" airline fitting) and with a control knob to reduce air if desired, is the most capable in most situations. It is the air bubbles which move water into the growth compartment and up the growth surfaces, and also supply carbon dioxide (CO2 in the air) to the surfaces, which allow algae to grow in the filter. Make sure to put the air pump above the aquarium so that it will not drain any water if it shuts off.


Comes with 2 red (660 nm) 3-watt LEDs, which are attached to a heat sink inside the cover; the cover gets warm on the outside. 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). The LED never needs replacing.


The HOG1 growth surface will need to be cleaned every 7 to 21 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 bubbler with a toothbrush. No hard scraping is needed; just brush it with a toothbrush. The Green Grabber growth surface is permanently glued to the inside cover using epoxy, however a few of the Green Grabber particles will dislodge during the first few cleanings, which is normal. Cleaning the growth surface, bubbler, and the inside cover takes about a minute with a toothbrush.


Visit the Santa Monica Filtration Website for the full description: