Canister filter vs reactor? (What is a reactor?)

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ScubaSkeets

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Hi folks!
The longer I am in this hobby (a whole two-three months), the more I realize how little I know.
I am using a magniflow 220 canister filter. It is stacked with black sponge, carbon, bio-balls, ceramic rings and polishing filter. I also added a bag of seachem deniitrate. I am also using a hang on back protein skimmer. I also have live sand and live rock.
Now, up until a few days ago, I thought that was sufficient. However, now I'm not so sure. Now, the more I read, I'm realizing most(?) people use a media reactor instead of a canister filter. (Or a sump?)
I just cannot wrap my head around what exactly a media reactor is and what does it do that my canister filter and protein skimmer does not.
Can someone please explain the differences?
Thanks!
 

Peace River

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Another way to look at this is to think about the three primary types of filtration that are often used in aquariums - mechanical, biological, and chemical. A canister filter is a (usually) plastic container that can perform any of these types of filtration depend on how they are setup - they do some of these better than others. Canister filters do have draw backs, but can be used effectively with some tanks. Reactors typically focus on a specific type of filtration. Additionally, a sump is a box that provides a place for extra water and to give space for any (or all) of these types of filtration. I encourage you to read more about these three types of filtration and I think it may help you get your head around the concepts - good luck and feel free to ask questions along the way!
 

salt2salt

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I have use 2 reactors (gfo/carbon and bio-pellets) in my sump. I use different flow rates in them. The output of one goes into my skimmer intake area (bio-pellets) The output of the outer (carbon) goes to the main return area. Reactors are great for fine tuning your filtration system.
 
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Billdogg

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A good example of a easy to use reactor is the TLF (two Little Fishes) 150. I've used one for many years (25+?) for GFO (Granular Ferric Oxide) as needed for issues with PO4 (phosphate). When in use, the water flows up through the GFO so that it tumbles just a little at it's surface. Any more than that and it can grind itself up into dust that can irritate your corals. Remember that all living organisms need a small amount of PO4 for basic metabolic purposes so your goal IS NOT a reading of 0.0, but rather somewhere in the .03-.05 range. Higher than that can promote algae growth, lower can inhibit growth.

I also use a BRS reactor for carbon. I run it on reverse flow so that the water pushes the carbon down so that it does not tumble at all. I run it 24/7/365 and have since I started with marine tanks in the mid '80's. It is very useful for removing toxins and DOC's (dissolved organic compounds) that can cause the water to look yellowish.

Many people use a canister filter, and although it can do almost the same thing as a reactor (or two), they can become a maintenance nightmare and will actually promote algae growth as trapped detritus starts to decay. If you are willing to clean it (weekly?) it will be just fine however. I used a HOB filter and a canister on my 60g cube for 22 years and was able to keep pretty much anything I wanted other than Acropora sp.

Having a sump can greatly simplify your maintenance as well as provide a great place to hide all the things you really don't want to look at in your main tank. Heaters, reactors, and skimmers are good examples of "sump stuff".
 

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Things have changed a lot over the years .
A sump is the most ideal giving more room for add ons such as skimmer placement , heater , place to hide heaters , gfo reactors etc.
A canister filter can work but a strict cleaning routine is required
Using as little inside as possible in terms of media ( bio balls , ceramic biological blocks etc were only said to cause issues later )
 
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ScubaSkeets

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Thanks for the replies!
However, im still not understanding the differences between a reactor and a canister filter. Here is a diagram I found of how a reactor works:

Media-Reactor-Small-1.jpg


Looks like the water comes in and goes to the bottom and then rises through the media until it reaches the top and then returns to the tank, no?
(I'm sure different ones do things differently, but that looks like the basic concept)

Now, here is a diagram of the magniflow 220 canister
2503699-Back-1.jpeg


It looks like the same concept. Enters. Goes to bottom via tube. Rises to the top, passing filter media,, and then returns to the tank. They are both enclosed. What cleaning and or maintenance needs to be done on the canister filter that doesn't need to be done on the reactor and why?
 
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salt2salt

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Thanks for the replies!
However, im still not understanding the differences between a reactor and a canister filter. Here is a diagram I found of how a reactor works:

Media-Reactor-Small-1.jpg


Looks like the water comes in and goes to the bottom and then rises through the media until it reaches the top and then returns to the tank, no?
(I'm sure different ones do things differently, but that looks like the basic concept)

Now, here is a diagram of the magniflow 220 canister
2503699-Back-1.jpeg


It looks like the same concept. Enters. Goes to bottom via tube. Rises to the top, passing filter media,, and then returns to the tank. They are both enclosed. What cleaning and or maintenance needs to be done on the canister filter that doesn't need to be done on the reactor and why?
The water flow is basically the same but canister filter use multiple types of media. a reactor uses just one type media. Gfo, carbon, bio pellets all need different flow rates and have different lifetimes. Canister- best for freshwater. Reactors best for saltwater. I don’t know anyone with a reef tank that uses or would use a canister filter.
 
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Billdogg

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The sponges on a reactor are fairly coarse so they trap little, if any, detritus while still keeping the media in place. The reactor will have no biological filtration and is usually dedicated to just one type of media due to the different rates of flow required for optimal use and the rates at which they are used up.
 

salt2salt

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The sponges on a reactor are fairly coarse so they trap little, if any, detritus while still keeping the media in place. The reactor will have no biological filtration and is usually dedicated to just one type of media due to the different rates of flow required for optimal use and the rates at which they are used up.
The sponges in a reactor a just to keep the media from leaving the reactor. They aren’t meant to do any filtering of the water.
 
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ScubaSkeets

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Ok. So the main difference is the media reactor uses one type of filtration and the canister filter uses multiple types of media filtration, correct? The canister is the "jack of all trades" and the reactor is the "master of one".
How is one type of filtration media better than multiple types of filtration media. Can you just use a canister filter as a media reactor if you only put one type of media in the canister?
 

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Ok. So the main difference is the media reactor uses one type of filtration and the canister filter uses multiple types of media filtration, correct? The canister is the "jack of all trades" and the reactor is the "master of one".
How is one type of filtration media better than multiple types of filtration media. Can you just use a canister filter as a media reactor if you only put one type of media in the canister?
If you didn’t have a sump or a media reactor
Essentially you could put that same media in a bag that comes with most and put it Inside the canister .
as mentioned above , the only thing to consider is some media comparing carbon to gfo
Different flow rates to work efficiently

2 totally different pieces of equipment with different purposes.
a canister filter is meant to mechanically filter all bad particles
A media reactor is used to polish water with what ever media you choose ( different media for different purposes )
 
AquaSD

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Ok. So the main difference is the media reactor uses one type of filtration and the canister filter uses multiple types of media filtration, correct? The canister is the "jack of all trades" and the reactor is the "master of one".
How is one type of filtration media better than multiple types of filtration media. Can you just use a canister filter as a media reactor if you only put one type of media in the canister?
They’re both very similar but the media reactor is better at forcing water through all of your media (I.e Carbon of gfo) whereas a canister may not do it as efficiently. Canister filters are also a pain to clean and maintain compared to a reactor which is very small. In this hobby you will often see people using a sump, which is essentially doing the same function as a canister filter, and they will have a separate media reactor somewhere in it which will usually contain carbon or GFO
 

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Sure you can, but you will be wasting a lot of media in the process. BRS suggests1 tablespoon/4g with an increase to 2tbl after a couple weeks if PO4 is still a problem. Using too much will strip the PO4 from the water way to quickly and cause more harm than good.

I suppose if you wanted to you could stuff a canister full of carbon, but that, too would be wasteful because you'd end up tossing perfectly good carbon every week when you clean out the canister filter sponges.

As I said in my first post - you can, indeed, use a canister filter. I did for 22 years. I also used a TLF 150 for GFO on the same tank so that I could maximize the efficiency and minimize the waste for the relatively expensive GFO. The canister served primarily as a place to have extra biological filtration. It was a royal PIA to clean and I don't miss it at all.

FWIW - I have several eheim canisters and a perfectly good FX5 sitting in boxes in the fish room. I do use one of the Eheims full of nothing more than pillow stuffing on my mixing barrel to clean out the gunk that sometimes forms in it.

There are better ways to skin this particular cat, but if you are set on using the canister, use it.
 

salt2salt

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Sure you can, but you will be wasting a lot of media in the process. BRS suggests1 tablespoon/4g with an increase to 2tbl after a couple weeks if PO4 is still a problem. Using too much will strip the PO4 from the water way to quickly and cause more harm than good.

I suppose if you wanted to you could stuff a canister full of carbon, but that, too would be wasteful because you'd end up tossing perfectly good carbon every week when you clean out the canister filter sponges.

As I said in my first post - you can, indeed, use a canister filter. I did for 22 years. I also used a TLF 150 for GFO on the same tank so that I could maximize the efficiency and minimize the waste for the relatively expensive GFO. The canister served primarily as a place to have extra biological filtration. It was a royal PIA to clean and I don't miss it at all.

FWIW - I have several eheim canisters and a perfectly good FX5 sitting in boxes in the fish room. I do use one of the Eheims full of nothing more than pillow stuffing on my mixing barrel to clean out the gunk that sometimes forms in it.

There are better ways to skin this particular cat, but if you are set on using the canister, use it.
Stay away from tlf 150 as they are junk. The seals are the worst and are leaking sives. There are much better cheaper ones out there. AquaMaxx has worked flawlessly for years on my system.
 
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Billdogg

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Stay away from tlf 150 as they are junk. The seals are the worst and are leaking sives. There are much better cheaper ones out there. AquaMaxx has worked flawlessly for years on my system.
Actually, I have 2 TLF 150's. Never had a lick of trouble with either one. IMHO, they are darn near indestructible But YMMV. There are plenty of other options out there.

And FWIW - the aquamaxx is $60, the TLF 150 is $44 from BRS
 

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Hi folks!
The longer I am in this hobby (a whole two-three months), the more I realize how little I know.
I am using a magniflow 220 canister filter. It is stacked with black sponge, carbon, bio-balls, ceramic rings and polishing filter. I also added a bag of seachem deniitrate. I am also using a hang on back protein skimmer. I also have live sand and live rock.
Now, up until a few days ago, I thought that was sufficient. However, now I'm not so sure. Now, the more I read, I'm realizing most(?) people use a media reactor instead of a canister filter. (Or a sump?)
I just cannot wrap my head around what exactly a media reactor is and what does it do that my canister filter and protein skimmer does not.
Can someone please explain the differences?
Thanks!
My tank has been running for 5 years with just a canister filter and skimmer so it can be done.
 
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ca1ore

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This is funny ....

The only difference between the ‘cannister filter’ and a ‘reactor’ is that the former has a built in pump and the latter does not. Each is simply a way to contain various filter media. Either can be used or misused.
 

chicago

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just found this thread. and wondering if anyone hear has ran GFO through a canister filter.. I have a colbalt canister filter... filled it with flos and put gfo..rowaphose in some bags and put between the trays in the canister filter...
 
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