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SunSun Hw303B 370GPH Pro Canister Filter Kit with 9-watt UV Sterilizer | 370GPH, 9-watt UV Sterilizer

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Availability: 18 left in stock
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Arrives Monday, Aug 31
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Features

  • HW-303B Pro Filtration Kit, Good for up to 100 gallon aquariums
  • Flow rate: 370 GPH (1400L/Hr)
  • Dimension: 10.5" L X 10.5" W X 16" H
  • Pro Kit Includes Canister Filter w/9 Watt UV, 3 White Filter Pads, 1 Blue Coarse Pad, 3 Media Baskets
  • Includes 1lb of Premium Filter Carbon, 1lb of Ceramic Rings and 1 Set of Bio Balls

Description

The Sun HW-303B external 4 stage canister filter is ideal for tanks up to 100 gallon. It handles up to 370 gallons per hour. The Sun HW-303B includes filter pads, hoses and all the parts you need to get started. The three flexible media trays allow you to add other filtration media such as Sun Sun's activated carbons, ceramic rings or bio-balls to achieve excellent mechanical, chemical and biological filtration. A built in 9 Watt UV sterilizer helps control algae spores/bacteria and promotes clear water. The HW-303B canister filter also has a convenient self-priming pump that eliminates the need for manual siphoning.

Product Dimensions ‏ : ‎ 12 x 12 x 20 inches; 16 pounds


Item model number ‏ : ‎ HW-303BPro


Date First Available ‏ : ‎ August 6, 2014


Manufacturer ‏ : ‎ SunSun


Best Sellers Rank: #77,216 in Pet Supplies (See Top 100 in Pet Supplies) #372 in Aquarium Filters


#372 in Aquarium Filters:


Customer Reviews: 4.3 4.3 out of 5 stars (1,377)


Item Weight: 16 pounds


Manufacturer: SunSun


Item model number: HW-303BPro


Date First Available: August 6, 2014


Item Package Dimensions L x W x H: 18 x 14 x 11 inches


Item Dimensions LxWxH: 12 x 12 x 20 inches


Brand Name: SunSun


Target Audience Keyword: fish


Directions: SUNSUN 303B canister Filter


Warranty Description: 180-day warranty, excluded UV lamp


Model Name: HW303B PRO


Color: White


Size: HW-303B Pro


Age Range Description: Adult


Included Components: Filter, Filter accessories, UV lamp


Specific Uses for Product: Indoor


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Aug 31

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To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Great value.
The Sunsun Hw 303B is great. Just finished setup in my marine tank. Read the reviews and tips. Mostly about using silicone lubricant (do not use Vaseline it will dry out the seals and crack them use silicone food grade lubricant only) on all the seals and purchased some of that as well. Turns out the company must be listening because all the seals were already lubed sufficiently from the box. Setup went very well with no leaks and it’s very quiet. I had modifications I had to do and the parts they supplied for the send and return were just what I needed with some careful thought. Be careful if you need these parts the cheaper ones may not come with them. They are less expensive because they don’t include the various nozzles, hoses and fittings. The only glitch I ran into was a big one if I hadn’t had some experience with these filters previously. The pictures I have supplied show the indicator for the uv light. This is what shows you the light is on or off. It’s just a plexiglass shaft that goes from the light chamber inside to the top of the unit. 1st pic shows it (circled in red) on the inside. It should be flush to the bottom of that area. 2nd pic shows it topside(again flush to the top surface). This piece was not in the proper position and would not allow the inside glass cover for the UV light to properly seal at the bottom or as in pic 3 the lock to properly engage fully. It took some doing to get it into its proper position but it finally popped in and allowed the glass cover to seat properly and the lock (shown in pic 3 circled in yellow) to fully engage over the flange of the cover. Had I not seen this it could have sent water into the light chamber and outside of the unit, frying the light and possibly shorting out the entire thing. Maybe worse since water and electricity don’t have a history of working well together. 4th pic is the final setup. I put a bin under to catch water in case of leakage as some suggested but so far it isn’t needed. It’s dry as a bone. Short of that I’d definitely recommend this unit for a small tank but take your time with setup, think things through and watch a few YouTube videos to avoid the pitfalls. Update as of 1/17/2024 : Still running well and zero leak issues. UV still functioning as well. Has developed some noise. It’s definitely noticeable but tolerable. Tried all the fixes recommended for canister filters on Google and YouTube to no avail. May try replacement of the impeller. Otherwise it’s performed diligently. Update 4/30/2025. Still going strong. Zero leaks the whole time. Never got around to replacing the impeller either. Still at the same noise level and I’m okay with it. ... show more
Reviewed in the United States on June 27, 2022 by Kevin P.

  • No leaks, no need for metal hose clamps, and compatible with Datoo in-line external heater
Overall I am happy with this filter, but I am new to canister filters and it’s only been a week running. I however am not new to keeping an aquarium and have used sump systems and hang on back filters on and off for over 30 years. I ended up purchasing the sun sun after reading many articles on best filters, the sun sun customer reviews, and watching YouTube videos on maintaining them. My experience so far is positive. One of the zippered mesh bags holding the ceramic rings was torn, but that’s an easy fix with needle and thread- the bag is not really needed anyway. Everything else was in great condition. The instructions are short and you have to read into them, but all in all they are okay if you have good problem solving skills and an imagination. One thing I read about often is leaking of hoses due to the plastic fittings provided with the filter, and compatibility issues with in line heaters. I purchased the datoo inline heater (I think it’s a sun sun one with a different name- it monitors in Fahrenheit instead of Celsius). I had zero compatibility issues and have experienced no leaks. It’s almost unbelievable because so many experienced aquarists are reporting leaks and the need for metal clamps. I’ve had none of these issues. Been holding my breath and set up everything in buckets to catch the water if the hoses should fail, but all is dry. I did have to cut about 3-4 inches off the end of the intake tube attachment because it was too long for the height of my aquarium. Two extensions to this tube are provided, so no worries if I were to take off too much. Otherwise, no other issues. Note: not all of the Sun Sun canisters have a UV light and come with filter media. I purchased the 303B and it came with both. Overall 4 star rating is because it’s only been a week running. Update: let me remind you that this is my first ever canister filter. Its been a couple of months now and no leaks or even hints of a leak. As far as I can tell, there is no need to go out and buy metal hose clamps (which I did based on reviews and ended wasting money). Easy to clean- no problems removing and replacing any of the filter baskets. For those of you who have never used a canister filter I was worried about how I was going to remove the hoses without all the water siphoning away-there is a lever that seals the hoses off and releases them from the lid of the canister. The water remains inline and I don't have to worry about the heater burning out (although I did unplug it and wait a bit before my maintenance of the canister). I have amended my rating to five stars. Great price, great performance, easy to maintain. ... show more
Reviewed in the United States on April 11, 2020 by Coocoomunga

  • Simple, whisper quiet, massive and circulating quite a vol. SIMPLY AWESOME! =v)
Oh my! This filter is fabulous. Comes with all the stuff needed if you will. I cant say nothing bad about this. The propeller shaft rod is ceramic???! Just awesome. I use it with the biohome filter media in couple of upper trays and also using very bottom part of the actual canister as a housing for few ceramic and biological media placed only in 1 level so it wont interfere with the first bottom tray. This thing is amazing. ~40 gallon aquarium kept crystal clear. Strong water flow, just waiting for biohome media to prime up and start taking the nitrate away without the need for water changes. Best part is the price of this filter from the seller. This is way beyond a bargain or a good deal. Shipping needed to be covered but im still happy I got this quite big if not HUGE canister filter for the third of what they offer you in local pet stores. Its literally amusing how small and expensive their stuff is. We know the physics and the common sense, to keep the filtration of an aquarium, you want as big canister as possible, especially if youre getting it for aquarium with a volume. Im very pleased with the seller, shipping and the filters performance which Im also aware that major role played by the type of the media you put in there. But the filter plays 50% role itself too. So, Thanks the seller for being on amazon and offering such a priceless deals! ... show more
Reviewed in the United States on October 10, 2015 by Emerther

  • Impressed
I had been battling a bacterial bloom in my 55 gal. tank and getting nowhere.I decided to give these Sunsun filters a try after reading the reviews here and online. So I ordered the 303b with UV light along with the 603 pre filter canister (no motor) and some additional bio media. Both canisters seem to be well made and pretty sturdy, as for the intake and discharge tubes the plastic not to bad but does feel kinda cheaply made,the hoses on the other hand are top notch. Getting everything put together was easy, getting it primed was not, I filled both canisters with tank water up to the top plate and closed the lids, even with water already in the filters it still took about 10 minutes of hitting the priming button to get the hoses full, once full I plugged in the filter and it started to push water and air out, tilting the filter back, forward and side to side will get any remaining air out. Now to the good part, this filter is quiet and has a pretty good flow. Within 12 hours after setup my water is as clear as glass, I'm planning on purchasing a new tank this Christmas and Sunsun is going to be what filters it.... btw if your interested in how this system works, water flows down to the bottom of the 603 and gets pumped up through 3 layers of mechanical media and then back to the bottom of the 303b where it get pumped up through your biological media and back to your tank, very simple and effective. ... show more
Reviewed in the United States on September 8, 2016 by Fishy Eye Rick

  • Very Satisfied
Received one of these with a used tank I bought off Facebook market place. Was my first canister filter ever. Have since bought a few more of the same 303b model for other tanks in the house. They are so much better than HOB filters! Practically zero noise since the output is below the waterline. Definitely messier to clean than HOB but seem do a better job with their purpose: filtration. There also seems to be a lot less water evaporation on my canister tanks - glass hoods with less/smaller holes. Key things I have learned: -Fill the canister up fully with tank water before powering on -make sure both intake and output tubes are fully submerged when powering on. If output isn’t submerged, air will get in and you won’t get siphon action -if you have a planted tank, unless you are changing monthly, don’t use charcoal. Charcoal cleans out some of the good stuff needed to “feed” plants. If you don’t replace charcoal in timely fashion nasties leach back into your water -Purigen is a great charcoal replacement -if you put a floss pad and coarse foam on the same tray expect some “melting” of the floss -when changing media, pull out the impaler and wipe it down -when cleaning, take it outside or to the bathtub as the lid hides water that emerges when tilted anyway (and with the light bulb it must be titled to set down) I don’t use the UV feature very often but it does work to eliminate algae blooms. My hand-me-down filter is at least 18 months old now and works as good as my brand new ones. All brands seem to be made of plastic. Haven’t had any issues. Replacement parts are readily available so entire canister wouldn’t have to be replaced if a component does go wrong. ... show more
Reviewed in the United States on February 9, 2020 by Zyla

  • NIGHTMARE - I DON'T RECOMMEND!
I never write reviews but I had to for this. This filter was a NIGHTMARE. I bought this for a turtle tank after our cheap HOB filters just weren't doing the job anymore since the turtle has gotten bigger. I did my research and I kept seeing that a canister filter is the best to have with a turtle. I do not want to spend $200 or $300 on a filter so when I found this one with all the good reviews it had for a really good price I decided to try it. It arrived in good condition. Was difficult to set up (directions are horrible) and the priming was INSANELY horrible. Took forever to prime. The big "priming" button isn't worth anything. (Didn't help that it's pretty tall and difficult to get into the cabinet under our tank either). After figuring everything out it worked fine for about 6 weeks.....until we cleaned it. After that and setting it back up again, it never worked right. Took forever to prime again and I absolutely COULD NOT get the air out of the thing. I did literally everything I could find to troubleshoot: Took it apart again and cleaned the impeller; capped off the skimmer; cut a piece of leftover tubing and fitted it over the connections on the intake tube (that didn't work so I also tried electrical tape over every seam in the intake tube as well as each connection from the U hook that goes into the tank to the tubing and from the tubing to the O ring that goes into the filter itself); made sure the other seam on the intake tube was under water; pumped the "priming button" a hundred thousand times. It would work fine for a few hours and then went back to a trickle coming out of the out-take tube (the tube that goes back into the tank after the water has gone through the filter.) Finally, it stopped working all together. It's just a terrible design....the intake tube seams are horrible and the intake tube is too small and the impeller just doesn't seem strong enough to pull the water all the way from the tank, through the filter and back up the tubing into the tank. And the filter just COULD NOT get all the air out. I contacted Amazon and I'm returning it. (Not getting a full refund because I used it, but better than nothing). I bought a Fluval HOB filter for tanks up to 110 gallons (our tank is 55 gallon and 1/2 to 2/3 full but for a turtle you have to get two to three times filtration because they are messy critters) that has basically the same type of filtration that the SunSun had (sponge, carbon and ceramic rings, minus the UV light). So far, the Fluval HOB is 150% better than the SunSun canister. Intake tube seams WAY more snug (I put electrical tape on them anyway to be safe); intake tube WAY bigger; water flow through the filter is awesome (the water doesn't have to travel up a skinny plastic intake tube, through a U, through tubing, through a filter below the tank, back UP more tubing, over another U and into another skinny plastic tube with some small holes in it!!!) All in all, very sorry I bought the thing and I don't recommend it. ... show more
Reviewed in the United States on May 27, 2016 by NJ2AZ2008

  • Great canister filter at an affordable price
Ordered this Sunsun 303B for an outdoor turtle habitat. This is the first canister filter I have owned. Package and boxing material were damaged in several places including on the inside with the accessory box being damaged. It appeared that this was perhaps a used/damaged and returned filter. However after unboxing and setting up, everything worked perfectly. Setup was very easy. Canister is maintained outside for an elevated turtle habitat. There is minimal noise/no noise from the actual canister. There is more noise from the waterfall effect of the outflow diffuser than there is from the canister. Suction is excellent and the inclusion of the 9W UV light has done a fantastic job of killing and eliminating my green algae water problem. I recommend running the light in 12 hour shifts or alternate day on day off. Canister has been running 24 hours a day for 7 days now and I conducted my first filter maintenance. I replaced filters as well as added additional biological filtration media and the clean up/replacement process was a breeze. Disassembling and reassembling the canister was essentially effortless. Highly recommend and would buy again. ... show more
Reviewed in the United States on July 11, 2021 by rich

  • Six years later still running
I bought this canister filter (almost) three years ago for my 50 gallon outdoor water lily tank with about 10 fish. So many things has happened in the past three years: water lilies flower and go dormant, we graduated and found jobs, we moved, racoon came and ate the biggest goldfish, the babies of the eaten goldfish grew up, house was refinanced twice, we had a baby and she's one year old now... Yet this filter is still running. I clean it every 3 months or so (or when I noticed the stream is weaker). It's not hard to clean but does require efforts. I'm about to replace the fabric filters for the first time because the white ones are starting to disintegrate. The filter is outside its entire life, under the sun in the summer and under the eve in the winter. I put some sort of plastic lid on it to block the sun, dust, or rain. Honestly I would be happy if it lasted 2 years. Would recommend! Update: the first photo was taken in the beginning of spring when I just cleaned the tank and moved it to the sunny spot, that's why the tank is so clean. The filter helps keeps the water clear but doesn't kill all the algae. The tank turns green very quickly. The second picture shows the tank today. Update Oct 2024. After my previous review in March 2021, the filter continued to run for another two years outdoors. In 2023 we decided to move all the remaining goldfish indoors, so we cleaned up this filter and stored it in the garage. One year later today, we decided the indoor fish tank needs a bigger second filter. So I got this one out, and after gathering filter media, hooking things up, and lots of elbow grease pumping air out (the manual pump is not as smooth as before), it fired up as strong as before. We'll see how many more years it lasts. ... show more
Reviewed in the United States on March 14, 2021 by Pressie

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