This HOG1 is a HOG Scrubber (tm) with 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 youll 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 instead; it will work the same. Or get the suction cup version; its not listed separately, so just order this magnet version and make a note that you want the suction cups instead.
This is 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 youve ever felt. A cactus might be sharper, but thats 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. Conventional 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 (dont let children play with them). Green Grabber surfaces are so good at grabbing algae and letting it grow that you may starting seeing tiny growth spots within hours, instead of days. And 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.
$149.99 USD (Use the shopping cart to tell you how much the shipping is, and be sure to click "display rates". If you dont have a zip code, enter "zip code" instead. Note that shipping outside of the USA will probably require you to also pay an import charge when it arrives. We cannot mark it as "gift". The lowest cost overseas shipping is generally USPS First Class Mail International. The size of the shipping box is 10 x 7 x 5 inches (25 x 17.5 x 10 cm).
This is a hand-built Hang-On-Glass ® (HOG) Upflow Algae Scrubber ® (UAS) with a Green Grabber (tm) growth surface, magnet version, 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 glass or acrylic is thicker than 1/2 inch (6.25mm), you can request the suction-cup version instead when you order this magnet version.
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
If your tank currently has very high nutrients, consider the stronger HOG1x 
No electrical parts go inside the aquarium; only air. And the air bubbler is already supplied (its sealed behind the growth surface), so you dont 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 an air pump that can pump at least 1.0 liters per minute (.04 cfm), which medium-cost air pumps can usually handle. Pumps that say they can handle 2 or more airstones/outlets, or pumps with 2 tubing attachments instead of one, will usually be more than enough. You can have as much air as you like, however; 5 lpm pumps are no problem. One powerful pump which works exceptionally well for a low cost is the Fusion 700 from JW Pet. It is quiet and has two outputs which are adjustable by turning the control knob. Another even more powerful and completely silent pump, although more expensive and without a control, is the Whisper 300 from Tetra. With either pump you will need to combine the two outputs into one to feed the scrubber, using something such as the "Tee" air line tubing fitting from Tom. 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 18 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.
The HOG1 comes with a 60 day warranty: Warranty is for replacement or repair only; not a refund. Costs for shipping back to us are covered if you are in the U.S. Costs for shipping back to us are not covered if you are not in the U.S., however we will pay for shipping back to you. In either case, you will need to ship the entire unit back to us before we can ship a replacement. Warranty is limited to repair or replacement, and does not cover fish loss, personal injury, property loss, or direct, incidental or consequential damage arising from the use of it. The warranty and remedies set forth above are exclusive and in lieu of all others, whether oral or written, express or implied. We specifically disclaim any and all implied warranties, including but not limited to lost profits, downtime, goodwill, damage to or replacement of other equipment and property, and any costs of recovering animals, plants, tanks or other aquarium related items and/or equipment. We are not responsible for special, incidental, or consequential damages resulting from any breach of warranty, or replacement of equipment or property, or any costs of recovering or reproducing any equipment, animals or plants used or grown with this product.
Can be shipped to any country; you can find shipping costs by using the shopping cart; be sure to click "display rates". If you dont have a zip code, enter "zip code" instead. Note that shipping outside of the USA will probably require you to also pay an import charge when it arrives. We cannot mark it as "gift". The lowest cost (but slowest) foreign shipping is generally USPS First Class Package International, but USPS Priority Mail International is better because it is faster and has insurance. The size of the shipping box is 10 x 7 x 5 inches, 25 x 17.5 x 10 cm).
This is the first Green Grabber (tm) algae scrubber available, and will be undergoing changes as improvements are found.
HOG1 size: Each cover is 5" wide x 6 5/8" high x 1" thick  (12.7cm wide x 16.8cm high x 2.5cm thick). It requires at least 5" (12.5cm) of water to operate in. The size of the suction cup version is the same as the HOG.5 suction cup version.