Hang On Glass® UAS®
Upflow Algae Scrubber®
Remove nuisance algae, nitrate and phosphate
- or -
Cultivate seaweed for feeding
1/4" (6mm) to 5/8" (16mm)
acrylic or glass walls
For more photos, click the Image Gallery button above or click here:
First three cleanings of the HOG3 in saltwater:
Unboxing and Shade Cloth Installation of the HOG3:
Comparison of HOG1.3 to HOG2 and HOG3:
New hard plastic magnet protector:
HOG3 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 be shipped to any country; you can find shipping costs by putting the item into the shopping cart; be sure to click "display rates"
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 is the first larger Hang-On-Glass version of the standard HOG.5, HOG1 and HOG1x algae scrubbers, which were the first HOG scrubbers available. This HOG3 offers much larger algae-attachment space to hold more growth between cleanings, and it is 2-sided instead of 1-sided because of the strings; 2-sided allows light to reach further into the growth. Also, stronger magnets attach to thicker aquarium walls up to 5/8" (16mm) glass or acrylic. If your tank is larger than a nano, then you can consider this model if you feed a lot.
This HOG3 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 HOG3 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 5/8 inch (16 mm). Not more. If your aquarium wall is 3/4" (18mm) it might work but you won't know until you try; it would be better to put the HOG3 in your sump instead; it will work the same.
Click the "image gallery" button above for more pics, or click here:
Compared to the HOG1.3
which look the same in size, the HOG3 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 HOG3 is designed for.
The large inside space of the HOG3 growth compartment allows for lots of build up of algae, but most importantly the 6 LED light provides the strongest photosynthesis of all the HOGs, giving it the best chance of out-competing the scrubber on your rocks. Also the 6 LED light grows green algae in situations where the lower power of the HOG1.3 or HOG2 would only grow brown algae. So this HOG3 model is great for aquariums that have been running for years and are showing signs of old tank syndrome, or in highly-fed predator or NPS corals tanks. Be sure to follow the special instructions on reducing the light during start-up (by covering the LEDs with a cloth) because the strong light and white surfaces will photo-inhibit initial growth in the scrubber if the light is not reduced..
The strings (ribbons) in the growth compartment of the HOG3 are the same strings that are in the SURF2 and SURF4, and are the heart of the ability of the scrubber to be able to use all the space for initial growth. The HOG1.3 and HOG2 have to grow outward from the textures before the open-area of the compartment is filled in; however the strings on the HOG3 allow this middle open area to start growing immediately, and to 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 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). Green-Grabber surfaces are so good at grabbing algae and letting it grow that if you have high nutrients 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, for the most photosynthesis (filtering).
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 5/8 inch (16 mm)
thick. This is the typical thickness range for most aquariums, and larger 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 (it's 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 HOG3 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 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). One powerful pump which works exceptionally well for a low cost is the Fusion 700 Air Pump
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 AP 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 Aquatics (which we include with the Fusion 700). Make sure to put the air pump above the aquarium so that it will not drain any water if it shuts off.
Comes with 6 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). The LEDs never needs replacing.
The HOG3 growth compartment 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 the bubbler with a toothbrush, and off of the strings with your fingers. Usually though you can just reach in an grab the growth. The Green-Grabber growth surface is permanently glued to the inside cover using epoxy, however a few of the Green-Grabber particles may 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.
This HOG3 comes with a 6 month warranty: Warranty is for replacement or repair only; not a refund. Costs for shipping back to us are not covered; 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 don't 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).
HOG3 size: 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). It requires at least 7" (17.5cm) of water to operate in.
"Great Product [HOG3]" -- Derek Johnson, Marlin, Texas, USA
"20 days... that's pretty wicked [HOG3] growth, and it seems like my glass algae has lessened" -- Trevor Janvier, Canada:
"My HOG3 is working good, and I want another one" -- Christian Aquino, Westechester, Illinois, USA
"Yes the [HOG3] is amazing. I have it in my ten gallon right now. No algae what so ever on the glass, etc. Water parameters are perfect!" -- Kelly Peissner, North Pole, Alaska, USA
"Been growing like a champ!" -- Mike Barone, Delrey Beach, Florida USA.
"Both the HOG3 and SURF8 are growing bright green algae; the nuisance algae in my tank is disappearing fast" -- Richard Neal, Santa Clara, California, USA:
Tom Verna in Southhampton, New Jersey, USA:
"So far, loving my new HOG3, definitely seem to have less algae on my glass, which is nice, not as much scraping as usual. I stopped using GFO, just before installing this, so the HOG3 was kind of, in a roundabout way to replace the GFO reactor. My phosphate has risen a little compared to running GFO (fresh) from 0.05 to 0.09 as expected, but my corals and I prefer this method. I'm now not focussing on low phosphate, but now focusing on just more stability with phosphate level. There's no swing in phosphate that is normally related to GFO life, so things stay really stable. The rise in phosphates is not causing any issues as the ATS has been picking up the slack quite well. When I got this I was pleased with how easy it was to install and use. It takes up very little space and fits just fine on the sump under the cabinet" -- IUfan on the INDMAS site:
"My two HOG3 units are very quiet when I put them one inch above the waterline. No other filters. Just the live rock, 2â€ť sand and HOG3â€™s. They are growing algae like crazy. I empty each one about once a weak (on different days) and they are FULL when I do. My tank isn't fully stocked yet, so I may need to get 1 or 2 more later. Meanwhile, inside the tank, I haven't had ANY nuisance algae since these HOGs kicked in, and I don't use any other filtration, and I've never done a water change. Needless to say, I am VERY happy with these. -- Sean Whelan, Brentwood, Tennessee, USA:
KaiserDeLeon in Manila:
LA Fishguys Jim Stime:
Mohamed Gomaa in Dubai:
"Tank is heavily fed and [HOG3] definitely seems to have made an improvement since the algae started growing" -- Jason Oneppo
"I'm getting good results from my SURF4 and HOG3.. It's bringing my phosphate down and starting to get some decent hair algae my tangs love" -- Dane Wilcox
Michel Claro's HOG3:
"Great deal! [HOG3]" -- polo1704 on ebay
HOG3 from Alanreef On the R2R site:
"I love how my four HOG3 units are constructed" -- Tim Caldwell
"All I can say about the HOG3 algae scrubber is WoW, I'm sure glad I saw it advertised on LA Fishguys youtube channel. It completely wiped out my severe case of Cyano Bacteria in 4 weeks, it is working like a champ. I was a little skeptical that it would work at first because it's very compact, but I am completely amazed on how great it's working. Thanks again for the great product" -- John Quezada
Nicolay Oganesian HOG3:
"The HOG3 that i purchased from you is doing really great. The first time it was full of green small rounded shape of algae, feels like jelly, i dont know what that is. The second and third week after that is full of green hair algae. Water parameters are great, with readings from hanna checker and salifert testers. I want to buy more of your products; I'm building a 5.2 meter reef aquarium" -- Yuppy Suhandinata:
"This is just one week after my first HOG3 cleaning; Is growing super thick green algae"
"And this is about 2 weeks growth, compartment completely full, nitrates are at 0, phosphates are between 0 and .25 per API, top layer was touching glass and was really yellow, when I pulled the layer off there was a ton of algae and it was dark green" -- Nathan P.
"It's been a little over a month since I installed two HOG3 filters on my 165g tank. Any algae that was growing on my rocks (just one spot) is now gone. Best part, so is any and all cyano!" -- 3Twinklets on the R2R site: