Review on Emperor 400 Filter?

Topic: I’m looking for a good “hang on the back” filter for my 60 gallon fish aquarium. I need reviews on the Emperor 400 by Marineland? It seems to be one of the top choices. Either that or an AquaClear. What is your review on the Marineland 400? o


*Awarded Answer
Posted by Chris W: These Emperor filters are some of my favorite. I use to run the aquaclears on all my tanks because they are the “best reviewed” on the internet. A friend kept arguing with me that Marineland bio-wheel filters were better. He gave me one to try for a couple months and I NEVER LOOKED BACK.. if you want to read more reviews here is an amazon link:

They are better! But there is a key variable that most people don’t know about. You have to let the bio-wheels (wheels that spin while filter runs) grow lots of bacteria and get super gross looking. They will turn a green color and look nasty. Most people change them out but that’s a MISTAKE. You need to let them get nasty and it takes months for them to get that way. Once they are super established these wheels are VERY EFFECTIVE and blow away other HOB filters on the market.

I have so much confidence in them that I have three running on tanks instead of canister filters that I bought. The reason these bio-wheels are so effective is because as the water runs out of the filter it runs over these wheels that are specifically designed to grow and harbor bacteria. That mixture of running water over that surface stuffed with growing bacteria WHILE ALSO being oxygenated is effective.

The Emperor series filters are better because they have “spray bars” which are little mists of water that help the bio-wheels spin around. Not a huge difference but it does help a lot more when forcing that water over the wheels filled with bacteria.

I could talk about filters for hours because I have thousands of gallons of aquariums and this stuff is my life! I highly advise the Marineland Emperor 400. The AquaClear 110 is a close second but… it’s basically just a really powerful pump and a perfect sponge pad. What I have done is take that same sponge pad and cut it in half and put it into the Emperor 400.

When you break it down.. all “hang on the back filters aka HOB” are the same. They have a pump and a canister than holds filter pad. As the pump pushes water into the canister it then runs through the filter pad as it exits back into the tank. Maybe some of the pumps are more powerful or the filter pads are different styles or the canister is bigger to hold more pads…

*The only HOB filter that is different is the Marinelands because they have bio-wheels too! They are a whole element past all the other competition. When you really sit down and study them that’s what you find! I highly suggest you buy the Emperor 400. It’s the top filter on the market!

  • I have a 55 gal with an emperor 400, I did a fishless cycle and it was complete. I bought 9 tiger barbs, 2 rainbow sharks, and 2 dwarf gourami and put in the tank and everything was fine. Ammonia 0, nitrite 0 and nitrates 10. After two weeks I decided to change out the filters that had been in there for over a month while it cycled and screwed the whole thing up and send it into them in the after two weeks I decided to change out the filters that had been in there for over a month while it cycled and screwed the whole thing up and send it into a mini cycle. I put one filter back in that was still wet day or two later and it seemed to help. It has been in there two weeks, with 2 new filters and a bag of seachem matrix, and my levels are back to normal. The question is when can I take it out safely and how do you change your filters later on to not cause this problem again. Also when it comes out I have another bag of seachem matrix to go in its place.
  • If you replaced the filter then don’t do that next time. I clean mine until the fibers start to fall part and by that time your tank has established bacteria on your gravel and hard surfaces.
  • If it were great, it’d be able to support it. You had too great of a bioload for what the tank could maintain. Fish should be added in short number spread over time.
  • dont throw away the sponges…replace them with ones that are more durable aka DIY
  • Aquaclear’s have that advantage…if u can find material that has the same type of sponge qualities u can cut to fit your own.
  • Ok fish people I got a question, should I build a canister filter (pic attached below of the style) for about $50 with no uv light or buy a sunsun 304b for $80 with a uv light. It is in addition to the Emperor 400 I am running on my 55 gallon community tank.
  • What’s a fair price on a full stocked and planted 40b with 2x Emperor 400filters, Tons of gorgeous and healthy anubias, lace rock, driftwood and plenty of healthy fish?


Posted by Grant H: Need some suggestions/help! I put an Aquaclear 110 on my 90 gal and was just sitting here with my coffee enjoying watching my fish. To my horror, I saw two of my neons get sucked up against the intake tube and die before my eyes. Granted, they are smaller but very healthy. I actually have two HOB filters going right now after changing out substrate last weekend. I’m now obviously afraid to run the Aquaclear but it does an awesome job. Any suggestions for what I can do to prevent any further casualties as I had planned to convert soley over to the Aquaclear after it had sat for a few weeks and then pull off the Emperor 400. Can I put something like filter floss or a sponge on the end of it without decreasing the effectiveness too terribly much? Even on the lower setting I still had a fish pulled in to it.

  • You very simply wrap it around the intake and make sure it is covered to stop the fish from getting sucked up
  • Use one of these, or make your own. Just be sure to clean it/ rinse it out during regular maintenance. They have a tendency to get clogged over time which will make your filter begin to prime/ burn up your pump.
  • I have an AC30 and I lost two small Harlequin Rasbora for the same reason. So I bought an AC20 sponge and use scissors to cut a slit and slide it in. Works very well and it only cost $2.
  • review emperor 400125 gallons of happiness! Just did a little fishie housekeeping and added one of my new aquaclear 110’s to the middle, will move the emperor 400‘s over to the 75 gallon in a couple days & add the second 110 on this tank. We shall see if it makes a difference.
  • My filter is not working. It is exactly a month old today and I only noticed because I’m going to do a water change. My damn air pump is so loud I can’t hear my filter.I’m doing my water change before I go to the store but any suggestions? It’s a 65US gallon aquarium and a Marineland bio wheel power emperor 400filter. I bought it discounted because the hinge on the lid was cracked but the filter should have lasted more than than a month!I know most re com end a canister but I am broke and need something in the same price range.

    Thanks in advance.


Posted by Ashley B: I’ve heard of people having issues with the bio-wheels not spinning or they stop spinning all together. That would be terrible if the wheel was really established and all of a sudden it stopped… That’s a lot of beneficial bacteria that would go to waste cause they take months to grow it.

  • That does happen to people but there is a trick to getting them to spin again. And if you get the emperor series (like we’re taking about) the spray bars ensure that the wheels never stop spinning. That’s sort of the reason for them.
  • I’d get a fluval 406 canister filter, and a new air pump 🙂 I have the 306 and it is shockingly quiet, very impressed, I hate loud aquarium equipment.
  • If you’re looking for another HOB, I’d recommend an Aquaclear. Super quiet and work great!
  • The emperor 400 can be a bit moody. Have you tried taking it apart and spraying water up in the magnet? Then when it’s full of water and plugged in play with the pickup /impeller. Pulling it up and down.
  • Return policy is 30 days and I’ve had it 32. Lol woman at the store is gonna let me exchange took it apart to check everything and it’s so new nothing is clogged or entangled. I was gonna exchange for canister but I’ve decided to exchange for the same one and order a canister online so at least I’ll have a back up.
  • Should I exchange for an a quackery rather than the emperor? I always thought this was a great filter from what I heard in the past.
  • I would get an aquaclear personally. If that is too expensive the aqueon brand hob filters are decent I have the 55/75 on my 46 and it works great. I swapped all the carbon sponge pads that it comes with for regular filter sponges added some ceramic and some purigen and it works great.
  • Just a few pictures of my tank. I just bought a marine land Emperor 400 Pro Series. up to 90 gallons. I have a 55 gallon. I’m thinking of getting another one do you think that would be okay for a 55 to have two of them.


Posted by Lacey F: I have a bit of an odd question about filtration. I’ve heard many time the classic “tell me about your filtration” and if you have an Emperor 400, then your filter is turning over so many gallons per hour. If I have a DiY Sump filtration, how would I determine how many gallons per hour are being filtered? Just by the size of the sump, or what?

  • The pump you use to return the filtered water should have a rating. That will tell you what youre turning over.
  • same thing applies….what pump is in the bottom of the sump? Mine has a 1000GPH pump on 1/2″ pipe so what~800gph ish.
  • Ok. The fiance built the sump years ago before my aquatic addiction. So I’m trying to play catch up and learn about it.
  • Set up my 75gallon..washed gravel inside and filled with water……emperor 400 bio wheel filter is running …what additives do I use. So many brands items to choose…suggestions please. I know I need chlorine remover. Seen stress coat mentioned here too. I am getting the Api water kit today…just need know what else I need while I cycle tank…thanks.


Posted by Dave N: When it rains, it pours.
So I posted about having to separate a fish into another tank because of aggression issues. I got that all squared away now.
Yesterday, I took apart my canister filter to use some of the media to help the new tank along. Routinely, I checked my impeller while the filter was dismantled to see if it needed to be be cleaned, and it did… Full of gunk. So, I re-assembled said filter after cleaning the impeller and surrounding housing.
Filter made horrible noises and despite best efforts of diagnose and repair, I had to commandeer a HOB filter.
So, got the Emperor 400 for my 75. Set it up, transferred all the seeding material I could from old filter to it. My tank is already well established. My question is will my tank still go through a “cycle” ?

  • depends on how much you were able to seed the filter and how much grabs hold. If its enough to process the new bioload of the tank then you might never see a spike or dip in any of your levels. If it still requires a bit more bacteria to build up to fully meet the demands of the bioload then you might see a mini cycle.. some ammonia rise… do a water change… or nitrites… maybe even cloudiness for a few days.. but it all depends on how much bacteria you saved initially to seed.
  • OK, ladies and gents, I’ve need of your assistance lol. I thought I was getting a 125+ but my MTS got the better of me and.. I now have a 65 gallon aquarium, a 40 gallon long and a 40 gallon tall. The equipment on the 40’s is undetermined atm but filtration on them will most likely be a Marineland Emperor 280 each unless you think a 400 would be more adequate? The 65 comes with two Penguin Biowheel 350’s so I will be running them at least for now. I’m currently unsure of inhabitants, substrates and lighting but will appreciate any and all input.
  • 40 gallon tall… angel or discus tank. 40 gallon long…. planted community tank but with only small schools of fish… like tetras.. white cloud minnows etc.. just small and a few corries. The 65… do an african cichlid tank.
  • I like the 40 long idea, planted/ small school community. Any further ideas on inhabitants in that tank? Cardinal Tetra and Long Fin Zebra Danio? Maybe a Gourami as a centerpiece, like a Pearl?
  • As far as Cichlids, I haven’t found a place in my heart for them yet, too agressive lol. I do like Discus though, maybe make the 65 a Discus centered tank?
  • Also.. the 65, coming with previously used boiwheels, will it need to be cycled over again or will it be fine once it’s up and running? It’s been in storage for 2 months without water via the previous owner.


Posted by Patricia K: Experienced fish keepers I have a question!

Thank you to the lady the other day who told me what breed the pair I have are (got them from someone who couldn’t tell me what breed).

We have 2 zebra danios. Clearly a male and female from size and colouration. I’ve just noticed this behaviour from the female as I was feeding them this evening. She is usually very active and greedy and confident at meal times! Now she’s slowly circling near the top of the tank. I gave her some flakes nearby and she ignored them! So out of character.

But on closer inspection she is HUGE and her egg sack has kind of squared off….is she about to give birth to eggs? I didn’t try and get them to breed or anything but I’ve started giving them a lot more variety in diet and freeze dried food. If she isn’t I’m worried about the out of character behavior. Water parameters normal. Thanks!

  • This topic is about the Emperor filter series…. why you posting here…
  • They don’t give birth, they are egg scattered, were she about to lay eggs she’d be near the bottom and being chased by the male, she looks to be bloated and ill


Posted by Harley R: so I made the upgrade to a canister filter, I ended up buying the Fluval 306. I was looking for recommendations on what to put in the media trays. so far I have just the stuff I came with it inside of it. biomax sponge on bottom, ceramic rings in the middle, then polishing pads with bags of carbon on top of the final layer. Any additional things I should purchase? and rearrangement recommendations?

  • Good question cause I just bought the 406 last night
  • I was torn between the 406 and 306, did you set up yours the same?
  • Take out the carbon, unnecessary and unless you change it out very often, it can be harmful to your fish. We packed ours (406) with biomax, the two large sponges and polishing pads
  • why is the carbon harmful?
  • Carbon is only useful for a couple weeks after that it starts to break down and become toxic to your fish.
  • The only thing carbon is useful for is to remove medication really.
  • ok ill take the carbon out, need to do some plant rearranging anyway.


Posted by Kevin F: It occurred to me, today, as storms with lightning and thunder passed through the area, that we could lose our electricity for a while. We are out of the woods now, since bad weather passed. I suppose I should’ve thought of it before, but how do you I protect my fish, if the power should go out for extended periods of time? Please don’t judge.

  • No worries. Tends to be an overlooked item in fish keeping. I never thought of it before but already had a generator around the house
  • We’re in Tacoma, WA where the power doesn’t go out frequently or long enough to warrant a generator. We had a 5 day outage several years ago (temps in the teen and twenties), but the house never got below 53 degrees.
  • emperor 400 filterBattery operated air pumps will work for 71 hrs at least.
  • It sadly, never even occurred to me. Thanks for the, albeit obvious, answers. And, for not, um, publicly, laughing at me.
  • Lol I had the same thought last week when some idiot texting and driving ran off the road and hit a transformer box knocking the power out for several hours.
  • Battery powered air pumps. And if your running a canister filter then take out all your bio media and put it right in the tank bc the canister will run out of oxygen in the water since its not pumping and your bb will die. Put it in the tank with battery air pumps and airstones and pile the medieval on top of it so the bubbles come up through it to keep water and oxygen moving for you.
  • Buy a backup generator.


Posted by Alicia H: Hi all – please don’t judge…I’m so bad with aquariums. BUT I want to get better which is why I’m here. I have a 10 gallon tank, which right now has quite a bit of algae and all on the glass and in the rocks.
How it got that way: not sure…exactly. I set up my tank this time last year and let it settle and acclimate. I used the water conditioner and treatment and such the way I was told. (I never could get the pH to be perfect…) I added my fish gradually and slowly. I had guppies. 2 zebra and the others had a yellowish orange belly. 2 of the 6 were female. Right off, 2 fish died. The two females had babies, and the tank did very well for a while. Then one day the babies weren’t there anymore. At some point during this happy time, I added elodea plants (not sure the regular name for that) which apparently came with a few snails, which quickly became a LOT of snails. Eventually though, I was down to only 2 guppies. Both male. The tank was still clear and pretty at this time.
Then comes Christmas break at school…I used a food disk that was recommended at Petco (sorry the only expert I had at the time…) and I came back from break and the tank had a ton of algae. Even after removing the disk, it was never the same. I was told this wasn’t supposed to happen with that disk. I have a emperor filter.
Sooo…I found my remaining fish a happy home with an experienced freshwater fish person. Drained my tank, but rocks now though dried, have algae and so does the glass.
I have not got a huge amount of money to spend on scrubbers and vacuums and things like that…and I don’t siphon water out. Ideally, I can set up the tank, get a fish or a something that eats all that algae, and a couple of fish, and run a successful tank. Thoughts? Ideas?

  • Wow. What kind of filter do you have? It is important for the fish for you to do regular water changes, also. Do you have a heater?
  • Have a filter that came with tank. I clean that regularly. Heater works but can’t regulate temp very well.
  • if you aren’t siphoning water out are you just adding enough to top off the evaporated water? I can’t imagine that would be too healthy for your fish, I actually siphon my tank more than I do clean my canister filters.. I’d suggest a vinegar and water scrub on the tank , maybe some hydrogen peroxide.
  • Ok so if I get my tank going again and with a filter have a beta, I need to do water changes? How often?
  • what size is your tank? ideal water change weekly 20-50% depending on what the tank holds.  were you cleaning your filter in tap water?
  • Disposable filters. 10gallon tank. I may be better off keeping the fish out and plants in.
  • If have any friends that have any tanks , don’t use things like syphon or some things see if you can borrow it
  • you could always go down that road, as you aren’t really required to do as much with a planted tank.. maybe some shrimp? they’re fun. if they’re generic hob filters you can rinse them in old tank water so you’re not constantly throwing them out and re buying as well :’)
  • if you had shrimp I would get a sponge filter, if just a planted tank I don’t think it’s really necessary. I change this cartridge once every 3-4 months but give it a rinse every 2-4 weeks depending on my bioloads.
  • Get a clean scrubbie that hasnt been used for anything else set ur tank in tub or sink scrub it out rinse with water.
  • First thing stop replacing disposable filters. You throw away a lot of your bacteria that u need to breakdown nutrients. Second thing to test your water. Some taps have a higher phosphate reading. If you can’t test it, take it to a fish store and let them do it. If your tank is near a window where natural sunlight can come in, move it or black out the window.
  • Btw get your filter cut a hole at the bottom and remove all the exhausted carbon. Carbon when full leeches all the bad stuff back in your aquarium. Carbon is better used with sw tanks.
  • Should the filer pad have zero carbon?
  • Yes that way you can use it over and over till it falls apart. Just rinse it with the water you pull out during a water change. Because the chlorine has evaporated in aged or condition water
  • If u feel like u need some sort or chemical filtration I suggest Purigen. 10$ on eBay. It does the same as carbon but is also a water polisher. It’s also reusable.
  • Should I still do water changes?
  • It’s a must to do water changes its the only way to replenish materials such as potassium iodine iron carbon etc(very minimal amounts).. Plus it removes nitrates.
    Some people have a full blown ecosystem where they don’t even do water changes. Big tanks are more stable because the high volume of water dilutes the ammonia and nitrates.
  • no problem. My 5 gallon crayfish tank has been running the same filter media for about 6 months now. No algae and I do water changes on it every 1-2 weeks
  • Water changes are imperative for the long-term health of any fish, shrimp, snails, whatever. There is no way around it if you care about the well-being of your pets.
  • Lesson #1: do not listen to advice from employees at big box chain stores. There are occasionally well-informed people who work at petsmart and Petco, but they are very rare. The training employees receive on pet care is a joke (this coming from someone worked at Petco once upon a time). I mucked up my first go at a 10 gallon based on “advice” from someone at petsmart. Best info I obtained was from books at the library written by knowledgeable hobbyists.
  • That is why I joined this group. Sadly the only fish places around here that I know of are the big box places.
  • Many of the great fish stores in my area have closed, leaving just the big chain stores, too, unfortunately. Forums can be great sources of info, hope we can help you out.
  • Just use a debit card to scrap the algae and the rocks just put in hot water
  • If it’s just a 10 gal put it in the tub fill with hot water and scrub with your debit card
  • Well if I were you I would start from scratch. This is what works for me. Clean your gravel and your tank, I also use white vinegar and water and a new sponge to clean everything and then I keep that sponge just for the tank.
    After everything is washed and rinsed put it back together. At this stage I would add about 3 to 6 Cory Dora catfish, these are cute little fish that clean up the bottom of your tank. So these are the bottom feeder fish, leave them in there on their own until you water comes right or cycles.
    Once your water comes right you can start adding more fish, guppies are a good top feeder fish, I usually have all males or all females otherwise the males are horrible to the females and they don’t last very long.
    Once you get them established you then need a few fish that are middle feeders, Rasbora, tetra, angel fish. It is very important to do water changes regularly I aim for once a week but go over sometimes and take out a third to a half and replace it with clean water. I am pretty brutal in I have two 200 ltr tanks and I syphon it out with a garden hose and replace it with cold tap water adding water conditioner before I turn the tap on. I really do not have any problems and have been successfully doing it this way for approximately 5 years, I do like to have algae eating fish and the last couple of years have introduced the big Apple snail which seem do a good job on the glass and don’t worry my plants too much
  • Please, please don’t add that many fish to the 10 gallon, OP. Even Corydoras and tetras both need 20 gallons as minimum. And angelfish get larger than an outstretched adult hand.Remember that the more fish, the more waste, the more algae.
  • Sorry I keep forgetting it’s a small tank, 😔so what would you suggest then, a pair of guppies?
  • A single male betta, with shrimp/snails. You could potentially get away with a group of 6 ember tetras, harlequin/lamb chop rasboras, Pygmy Corydoras or similar sized micro species, but it’d be on the very low end of their requirements.
  • The corydora I am talking about are little, can you get big ones? I tend to overstock my tanks but they do very well and certainly don’t have algae problems, I do water changes regularly.
  • Not sure what an ember tetra is, have never seen them over here, we only have a few variety here, neon, cardinal black skirt.
  • The Corydoras you mean are likely Corydoras aeneus. They’re normal size. Pygmy Corydoras are very tiny.Neons, cardinals and black skirt tetras are all far too big for 10 gallons. Again, ember tetras are much much smaller.
  • I don’t think we have any of those here, certainly not the cories as I love them and would have noticed. So what do you keep.
  • I have multiple aquariums of different sizes. My smallest is 5 gallons, which houses a male betta. I also keep single bettas in a 10.5 and 12 gallon, but have no other tanks below 20 gallons.
  • I only have community tanks, with various interesting fish and small groups of little fish, I will have to rehouse some of them if they get too big, I have a black knife ghost fish that is 18 inches long, he is approximately 5 years old now.
  • Oh and I only use canister filters they are brilliant in my opinion, hope this all helps as keeping fish is just a beautiful thing to do as a hobby.
  • To combat algae you need to know why it forms. In your case the likely culprits are:-Excess nutrients, like fish waste if your tank is overstocked.-Excess light.So, what you need to do is…-Reduce/remove nutrients. Stock more appropriately for your tank, and add low maintenance plants to out compete the algae for food.-Make sure the tank is only receiving an absolute maximum of 8 hours of light per day. You may need to reduce this further. This includes natural light, from nearby windows etc.Don’t buy fish to remove algae, deal with the source of the problem.
  • I think if you get a better filter like a Emperor series made by Marinleand you will be in better shap. The reviews on the 400 series are super high.