main difference between HOB and cannister filter?

[djmodifyd]

besides the obvious?
I currently have a HOB filter on a 60 gallon community FW tank.

Would it be benificial at all to get a canister filter?

thank you...i've searched and couldn't find a specific answer.

[krytan]

You can fit a lot more media in a canister.

[7itanium]

a lot more media... they are a bit more effective as well

the reason for this is mostly due to the increase in media-- and usually they have a higher flow rate compared to comparable HOB filters

[Star_Rider]

HOB's use the pump to pull water up the pick up tube.
many cannisters use siphon to bring the water to the cannister and the pump pushes the water up to the tank.

I personally think cannisters need more surface/media . for the bio media and mechanical filtration to work properly .
they do tend to move more water so subsequently they need more surface for the filter to remain effective.

[McLendon]

Canister filters are
Str8 mechanical filtration they do not let water bypass filter media.letting you custom stack with things like white dimond chips Ect and finer and finer filter pads to remove the bad stuff.but they do little in the way of Bio filtration
As they are air/water tight.with HOB filter you give up a lot of
Mechanical filtration
You gain Bio filtration do to them being open to the air

IMHO for FW tanks of
150gl and less HOB's will work fine.FW tanks over 150gl and any size SW I would use nothing less then a canster

[Kashta]

On a 60 gallon tank with average stocking, I would run a canister from the bottom and a HOB up top... both rated for something in the 75-100 gallon range. Start off with whichever filter you have, then watch for sales, discounts, or used equipment for sale over the following months to get the second filter.

I like canister filters best because they move more water and I can pack the media trays with whatever I want. But I also want a secondary HOB running for more biological filtration. I can stuff it with carbon temporarily to pull out meds without having to open up the canister for this. What I don't like about HOBs is they hold very little media and as soon as that starts clogging up, the water flows right over the top, doing no good whatsoever.

[247Plants]

Canister filters are
Str8 mechanical filtration they do not let water bypass filter media.letting you custom stack with things like white dimond chips Ect and finer and finer filter pads to remove the bad stuff.but they do little in the way of Bio filtration
As they are air/water tight.with HOB filter you give up a lot of
Mechanical filtration
You gain Bio filtration do to them being open to the air

IMHO for FW tanks of
150gl and less HOB's will work fine.FW tanks over 150gl and any size SW I would use nothing less then a canster

Not all completely true. Canister filters are NOT just for mechanical mechanical filtration, they do have bypass(not much though) and have great biofiltration(more room for media than a HOB).

HOB filters dont gain any benefits from being open to the air. Matter of fact all the media should be submerged in water in the HOB.

Main reason I have always used canisters, is that they dont make a lot of noise, and keep surface agitation to a minimum.

Canisters are available for all size tanks down to nanos. Really just depends on the application and personal preference.

[avionics30]

Canister filters are
Str8 mechanical filtration they do not let water bypass filter media.letting you custom stack with things like white dimond chips Ect and finer and finer filter pads to remove the bad stuff.but they do little in the way of Bio filtration
As they are air/water tight.with HOB filter you give up a lot of
Mechanical filtration
You gain Bio filtration do to them being open to the air

IMHO for FW tanks of
150gl and less HOB's will work fine.FW tanks over 150gl and any size SW I would use nothing less then a canster

This statement doesn't ring true with my experience. The only time that I use a HOB filter is if the tank is so small that you don't have a choice. Canister filters are biological power houses! The largest canister that I ues is the Fluval FX5 and all I use is ceramic bio media in it. Every try is filled with it. The only mechanical filtration that I use with the FX5 are the sponges that surround the bio media within it. I have no issues with particulates in the water or anything like that.

I read that a lot of people put a lot of emphasis on mechanical filtration. Yes, it's OK to have, but the bio filtration is far more important. All canister filters come standard with mechanical filtration. You shouldn't need to add floss, pads, etc. You're just going to clog up the filter faster. Put bio media in every tray. You don't even need carbon if you are keeping a reasonable maintenance program.

Keep your tank as natural as you can! Use bio media to the max and stay away from chemicals and all the other crap that costs money! Once you set up a canister filter, you shouldn't have to keep spending money on it. Just clean the sponges once a month! Bottom line, canisters offer more bio media surface area. That is all.

Best wishes!

[echoofformless]

I will add the following:

Canisters allow you unlimited flexibility in where you place your inlet and outlet. With HOB you're stuck with one configuration.

If you're running a planted tank, and/or you want less surface agitation for reduced evaporation, canisters allow you to reduce this factor.

Canisters (especially Eheim Classics) need far less maintenance and don't require costly proprietary media. In fact my Eheim Classics have never had any media replacement. I just rinse it every few months.

Physically I like the notion of less weight and less stress on the tank. Also requires less cut away on the back strip of your lid. Decreases evaporation and helps reduce risk of losing jumpy fish.


HOB's are generally less expensive to purchase, far easier to use and maintain.

HOB's are often better for systems where you want increased gas exchange - a lot of marine keepers like them over canisters due to the claim that they aren't as prone to produce nitrate.

[avionics30]

HOB's are often better for systems where you want increased gas exchange - a lot of marine keepers like them over canisters due to the claim that they aren't as prone to produce nitrate.

I'd love to hear the explaination behind less nitrate in an HOB.

[247Plants]

I'd love to hear the explaination behind less nitrate in an HOB.

More media in a canister to clog and break down into nitrates. Not to mention tubes and any other areas where mulm can build up and decompose.

[echoofformless]

More gas exchange. Supposedly the fact that there is surface agitation above the media allows some of the nitrate to dissipate. A canister is enclosed so this isn't allowed.

At least that is what a lot of reefers/marine keepers claim. Like I said originally, it's a "claim" so don't quote me on it. Though I can see it making sense for that reason, as well as the fact that there is a lot more dirt buildup over time in a canister system.

I love the idea of canisters being a nitrate factory for my heavily planted tanks.

I encourage it.

[Jalo Reefa']

Isn't surface agitation a good thing?

also, the idea that canisters require less maintenance is not one I am buying either. I've used both, and now with my overstocked rift lake tanks I pretty much use fluidized bed filters and the marineland Emperor series - I've never come across a filter that needed less maintenance or was easier to maintain than the marineland. I've completely gone away from canisters all together - all it takes is just ONE time to have an o-ring fail or a hose fail on you, have 75 gallons of water pumped onto your hardwood floor, and it will make you rethink canisters for the rest of your fish keeping life (take my word on that one!)

my rifties certainly haven't filed any complaints since I banish Eheim from my house forever, in fact I wouldn't be surprised if there is something to that nitrate theory, because I've had less algae issues far and away

[247Plants]

Surface agitation is bad for me because it promotes the outgassing of my precious co2. (not to say the surface of my water is unrippled)

I think people tend to go longer between maintenance on canisters vs. hobs. Probably more of a reason for more nitrates to be present.

True an o-ring fail or hose fail is horrible, but there are many other things that can spill water,, like a busted seam or a crack in the body of a hob. Its all a game of chance and there is no telling when any one part of a complex system will fail.

Understock and overfilter and you shouldnt have any problems.

[BoCoMo]

Canisters are better for aquariums with compressed CO2 systems as they can create less surface turbulence than an HOB (that will vent off a lot of your CO2)

[Jalo Reefa']

yeah, I see the point - I am setting up my first marine tank now and people are telling me I need to find ways to vent CO2, so I guess it all depends on what your goal is.

I do keep large, overstocked African Cichlid tanks and the conventional wisdom you would get out of reading this forum is you must have an awesome canister filter to do this successfully. I would argue against that conventional wisdom. There is more than one way to skin a cat. I love doing maintenance on my tanks, its a labor of love, but that doesn't mean I want to haul around gallons of water and gunk-ridden media. Aside from that, I openly admit that after my Eheim classic (considered holy on this forum, and I readily admit most are probably great) caused a catastrophy it just turned me off all together to that style of filtration.

[BoCoMo]

yeah, I see the point - I am setting up my first marine tank now and people are telling me I need to find ways to vent CO2, so I guess it all depends on what your goal is.

I do keep large, overstocked African Cichlid tanks and the conventional wisdom you would get out of reading this forum is you must have an awesome canister filter to do this successfully. I would argue against that conventional wisdom. There is more than one way to skin a cat. I love doing maintenance on my tanks, its a labor of love, but that doesn't mean I want to haul around gallons of water and gunk-ridden media. Aside from that, I openly admit that after my Eheim classic (considered holy on this forum, and I readily admit most are probably great) caused a catastrophy it just turned me off all together to that style of filtration.

Excellent post! Proof that there is no one right answer for everyone. I personally like performing maintenance as well so all I really use a filter for is catching debris. I like getting my oxygen & bio filtration from my plants (not easy for you to do, I bet any plants you put in get uprooted and/or eaten) steady water changes works wonders.

[Jalo Reefa']

indeed - I love aquatic plants, but the varieties of Africans I keep either turn them into lunch, or make life miserable by digging them up and "re-arranging their furniture."

Sometimes you have to look past your own inferences, another example when I say things like "I keep overstocked African Cichlid tanks" some on here probably think "oh no those poor crowded fish and their unhealthy environment." I actually do it to LIMIT AGGRESSION (which is effective) and keep them from bullying one another, and I compensate with an aggressive water change schedule and heavily bio filter (hence the fluidized bed filters)

this is the first time I've started a marine tank, and I've already learned SO MUCH from people here on AC... but I'm always suspicious when someone comes across as all-knowing or puts off the vibe that they are experts and nobody else can have a different approach. Thats why threads like this are so interesting to me, you usually get people who swear by their methods, which is fine... I just like seeing all the different methods

[247Plants]

yeah, I see the point - I am setting up my first marine tank now and people are telling me I need to find ways to vent CO2, so I guess it all depends on what your goal is.

I do keep large, overstocked African Cichlid tanks and the conventional wisdom you would get out of reading this forum is you must have an awesome canister filter to do this successfully. I would argue against that conventional wisdom. There is more than one way to skin a cat. I love doing maintenance on my tanks, its a labor of love, but that doesn't mean I want to haul around gallons of water and gunk-ridden media. Aside from that, I openly admit that after my Eheim classic (considered holy on this forum, and I readily admit most are probably great) caused a catastrophy it just turned me off all together to that style of filtration.

Indeed an excellent post.

Every tank is different and as such will have different needs. There is no hard line that says a canister is better than a hob or vice versa.

[avionics30]

More media in a canister to clog and break down into nitrates. Not to mention tubes and any other areas where mulm can build up and decompose.

This is where yank maintenance comes in... you have to do it! Amonthly cleaning is really all it takes on these filters.


More gas exchange. Supposedly the fact that there is surface agitation above the media allows some of the nitrate to dissipate. A canister is enclosed so this isn't allowed.

At least that is what a lot of reefers/marine keepers claim. Like I said originally, it's a "claim" so don't quote me on it. Though I can see it making sense for that reason, as well as the fact that there is a lot more dirt buildup over time in a canister system.

I love the idea of canisters being a nitrate factory for my heavily planted tanks.

I encourage it.

Nitrate does not gass off. If this were the case, we'd all be blasting air in to our aquariums to get rid of it and phosban wouldn't exist!


Isn't surface agitation a good thing?

also, the idea that canisters require less maintenance is not one I am buying either. I've used both, and now with my overstocked rift lake tanks I pretty much use fluidized bed filters and the marineland Emperor series - I've never come across a filter that needed less maintenance or was easier to maintain than the marineland. I've completely gone away from canisters all together - all it takes is just ONE time to have an o-ring fail or a hose fail on you, have 75 gallons of water pumped onto your hardwood floor, and it will make you rethink canisters for the rest of your fish keeping life (take my word on that one!)

my rifties certainly haven't filed any complaints since I banish Eheim from my house forever, in fact I wouldn't be surprised if there is something to that nitrate theory, because I've had less algae issues far and away


You said it yourself, you're overstocked! Maybe you need more filtration or a bigger tank? Just something to consider. I've never had a canister blow a gasket on me. You do have to pay attention to whay you're doing when reassembling them!

Best wishes!

[Jalo Reefa']

avionics, read all the posts please before offering an expert opinion on my stocking. I'm overstocked with 0.0 ammonia, 0.0 nitrite, and 0.5 nitrate... and no aggression, with aggressive species.

you might want to read the whole thread before educating the ignorants like me. Of course, the canister fail I experienced was my fault... I clearly can't read directions, and if its never happened to you it must be impossible.

haha - kind of post I was referring to at 1:57

[pinkertd]

We all have opinions, and yes, some shout their opinions louder than others.
I love my marineland filters and I use them on my 55, 72 and 75G tanks. I also have two AC 110's which come in second to the marineland. I would challenge many to get more worthwhile media in the AC than I get in my marineland. I cannot see where a canister would be any better on any of my tanks than what I'm doing now. And some people here recommend a canister filter along with an HOB. So what's wrong with two HOB's? I'm overstocked as well. I've never seen how a cannister works. I know it would have to just about gravel vac and feed my fish for me before I'd shell out a couple of hundred dollars for what I can accomplish for under $100. And I'm mechanically challenged, I don't have a lot of patience with machines and no one to ask to help. So all these factors go into the equipment purchasing decision for each person....or should. But until someone can tell me exactly how my tank would be better/cleaner when my water is already crystal clear and within normal range, or my fish healthier when they are never sick (knock wood).....I'm sticking with what I think are terrific filters for me....HOB. Now I might have to rethink this if I get a much larger tank, and take an evening class in parts and tubes and fittings and priming.....:grinyes:

[avionics30]

avionics, read all the posts please before offering an expert opinion on my stocking. I'm overstocked with 0.0 ammonia, 0.0 nitrite, and 0.5 nitrate... and no aggression, with aggressive species.

you might want to read the whole thread before educating the ignorants like me. Of course, the canister fail I experienced was my fault... I clearly can't read directions, and if its never happened to you it must be impossible.

haha - kind of post I was referring to at 1:57

First off, I am not providing an EXPERT opinion. I'm not a marine biologist. I'm an electrical engineer.

All I said was that YOU said that you were overstocked. Naturally any stocking that exceeds the "standard limits" for filtration will tax the filter and probably cause you more maintenance. That is a given. I use both HOB and canister. I have to clean my HOB way more than the canister. As soon as the HOB gets a bit congested, it starts bypassing. That is highly inefficient.

It's not very nice to call anyone, including yourself, ignoratnt. The word ignorant seems very demeaning. Everyone on this site is here to learn, including myself. I learn something new every day. I would hope that everyone that uses this site learns something! If you come here thinking you know everything, then this site is going to bore you out of your skull! You already know everything!! LOL!

As for your canister filter leak, I stated that you have to pay attention to when assembling the filter. You stated yourself that you failed to read the instructions. The instructions are part of paying attention. If properly assembled, you will not encounter a leak so massive that it would ruin your floors. Had you stated that you followed the instructions flawlessly and the canister developed a crack, then that would be a manufacturing defect that you had no control over. That would be nice information to share with those of us that have not encountered this defect and should be aware of. See the difference?

Bottom line, everyone experiences something different. If you take what you read on these threads as gospel, then you are setting yourself up for failure. Forums are places to share experiences and naturally some of those experiences are fact based. It's like reading Wikipedia. Do you believe everything that you read there? If so, you may want to reconsider. Wikipedia is a forum of sorts that allows people to apply input to the definitions found within. It's nearly a tabloid! LOL!

Sometime we all have to agree to disagree on some things and many of those instance occur in fish keeping. Yes, there are things that, in a perfect world, we should ALL do while maintaining aquaria, but do we do them? Probably not to the "T". You overstock. Well, that is against one of the cardinal rules of fish keeping!! DO NOT OVERSTOCK! Do I do it, only when I have to. Do I like it, no. Do I increase my maintenance practices when I am overstocked? Yes. It's that simple.

In closing, I don't think that any of my responses were out of line or false. If you do, I apologize and am willing to retract anything that I may have said that offended you or anyone else in this forum. Have a great weekend!

Best wishes

[avionics30]

We all have opinions, and yes, some shout their opinions louder than others.
I love my marineland filters and I use them on my 55, 72 and 75G tanks. I also have two AC 110's which come in second to the marineland. I would challenge many to get more worthwhile media in the AC than I get in my marineland. I cannot see where a canister would be any better on any of my tanks than what I'm doing now. And some people here recommend a canister filter along with an HOB. So what's wrong with two HOB's? I'm overstocked as well. I've never seen how a cannister works. I know it would have to just about gravel vac and feed my fish for me before I'd shell out a couple of hundred dollars for what I can accomplish for under $100. And I'm mechanically challenged, I don't have a lot of patience with machines and no one to ask to help. So all these factors go into the equipment purchasing decision for each person....or should. But until someone can tell me exactly how my tank would be better/cleaner when my water is already crystal clear and within normal range, or my fish healthier when they are never sick (knock wood).....I'm sticking with what I think are terrific filters for me....HOB. Now I might have to rethink this if I get a much larger tank, and take an evening class in parts and tubes and fittings and priming.....:grinyes:


Great points Debbi! Thank you!

[djmodifyd]

thank you all for the posts...its been alot of help!

[avionics30]

You bet! Sorry for hijacking your post. That was unintended.

Best wishes!

[Nutt]

One other thing I consider is the cost of mantinece.Canisters for the most part alow you to reuse most media where most hobs have cartiges that need to be replaced. Thus canisters have high inital cost and low maintnece cost hobs are the opisite. I use both I love diferent aspects of both! I also love sponge filters because of cost reasons, ease of use and high bio filtration qualities. Theres my two cents!

[mott]

I totally agree with everyone here that it's up to the individual use on what is better.
For me it's canisters 100% I inject co2 and don't want to waste any of it with the waterfall a HOB will cause. Another big time benefit is I only clean my canisters once every six months so my maintenance is mostly left to trimming and water changes. Canisters do need to have the o-rings lubed once and a while to avoid leaking 75 gallons on your hard wood floor.

[pinkertd]

One other thing I consider is the cost of mantinece.Canisters for the most part alow you to reuse most media where most hobs have cartiges that need to be replaced. Thus canisters have high inital cost and low maintnece cost hobs are the opisite. I use both I love diferent aspects of both! I also love sponge filters because of cost reasons, ease of use and high bio filtration qualities. Theres my two cents!

I stack foam blocks and use micron pad (all rinseable and reuseable indefinitely) prior to my cartridges so once the carbon no longer is active in the cartridge, my cartridges are additional mechanical/biological media and are rinsed and left in the filter. I use them for months and months, they don't get clogged because the coarse foam blocks catch the larger particles, so very, very little cost to me on media.

[Jalo Reefa']

weird, went back through my posts, never saw were I said I didn't read the instructions - I sarcastically remarked that AFTER you recommended I read the instructions. For that I apologize, sarcasm doesn't translate well on forums.

Sorry, I get frustrated when people don't read whole threads and comment on things that have been addressed in previous posts. I really don't think you would have commented on me being overstocked if you'd read my 157 post

[echoofformless]

In an overstocked tank with no plants I would personally use a HOB (and this is coming from someone who loves canisters.) With so much debris coming into the media, I would want a simple and fast complete throwaway sort of deal. HOB's provide this, even if it will cost a lot more money. Like I said, I encourage nitrate in most of my tanks because I'm a plant enthusiast. My filters rarely get any maintenance. The tanks are also rather understocked for this very reason. I go literally months without touching the insides of my canisters.

This I would not dare in a rift aquarium.

So in my estimation it's less an opinion thing as it is a system by system thing. Consider that I have two 5.5g betta tanks that have no mechanical filtration at all. It's purely botanical and manual.

[yhbae]

In an overstocked tank with no plants I would personally use a HOB (and this is coming from someone who loves canisters.) With so much debris coming into the media, I would want a simple and fast complete throwaway sort of deal. HOB's provide this, even if it will cost a lot more money. Like I said, I encourage nitrate in most of my tanks because I'm a plant enthusiast. My filters rarely get any maintenance. The tanks are also rather understocked for this very reason. I go literally months without touching the insides of my canisters.


This is true, that's why I tend to like the setup that focuses more biological filtration on the canister and mechanical on HOB on the same tank. I used to only use very coarse sponges in between media inside the canister. I still like this setup. :)

[mott]

I don't understand why people think HOB's are better at mech than a can. with most canisters there is little to no bypass for the water to flow through, especially Eheim classics, if you stuff the last layer with floss you have fantastic mechanical filtration much better than HOB's Imo. Most HOB's have huge bypass issues, I have yet to see one that has NO bypass.

[yhbae]

I don't understand why people think HOB's are better at mech than a can. with most canisters there is little to no bypass for the water to flow through, especially Eheim classics, if you stuff the last layer with floss you have fantastic mechanical filtration much better than HOB's Imo. Most HOB's have huge bypass issues, I have yet to see one that has NO bypass.

HOBs are not better than canisters for mechanical filtration. But HOBs are much much easier to clean than canisters. That's why I have both Eheim Classics and AquaClear filters on all tanks where I expect lots of blockage.

[Kashta]

The fact that HOBs get dirty so fast and need to be cleaned more often is also a benefit, not necessarily a drawback. Another reason to run both types on the same tank. When I actually see all the gunk that's built up already in my HOB, I also know it's accumulating the same way in my canister below. So it's a good reminder that makes me think (as I'm cleaning the HOB)... hmm, how long HAS it been since I last cleaned my canister filter?

[echoofformless]

I like that my canisters are gunky in my heavily planted systems - more nitrate for my plants! :)