Combining a Radial Filter with a Bio Filter?

[brendon 12]

So I am reading more and more about the benefits of Bio Filtration and Radial Filters. Being that I already am in the process of creating the radial filter ... might it make since to combine the two? Check out the diagram below ... seems to contain and slowly rotate the K1 media ... only drawback i can think of is maybe some of the solid waste getting stuck on the k1 media ... but I would this that would come of with time moving around.

Thoughts ...

[GaryD 1053]

Hi Brendon,

So I am reading more and more about the benefits of Bio Filtration and Radial Filters. Being that I already am in the process of creating the radial filter ... might it make since to combine the two?

You could......and that's what happens in the case of the Nexus 310 filter (although the layout is slightly different).

Where you would probably get an ever better outcome would be if you used the filter in your diagram as a combination radial flow separator and packed media filter......and have a separate moving bed bio-filter.

Gary

[brendon 12]

Where you would probably get an ever better outcome would be if you used the filter in your diagram as a combination radial flow separator and packed media filter......and have a separate moving bed bio-filter.

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When you say "packed media filter" are you talking about packing it with a filter "sponge" material?

Also, I saw your Queenslander design and noticed you put the biofilter off of the sump. If I went FT, Radial Filter, Bio Filter would I have enough gravity fed water flow to get out to all of my 5 grow beds. I am using a CHIFT (CHOP) system so gravity will feed my beds (FT waterlevel will be about 12 inches higher than the top fill line of the grow beds)

Thanks

Brendon

[silloth52 10]

hi brendon

i am using a chop2 system and i use a radial flow filter from the fish tank to the sump and a packed media filter from the sump back to the fish tank works ok especially with the amount of dirty water created by trout

[brendon 12]

hi brendon

i am using a chop2 system and i use a radial flow filter from the fish tank to the sump and a packed media filter from the sump back to the fish tank works ok especially with the amount of dirty water created by trout

silloth52 -

What is a packed media filter? Do you have a picture of yours that you can share? Is that the filter with the brushes (wire w bristles) stuffed into a bucket so the water can pass through and get thick partical filtration?

Thanks for the response

Brendon

[Earthan Group 594]

So I am reading more and more about the benefits of Bio Filtration and Radial Filters. Being that I already am in the process of creating the radial filter ... might it make since to combine the two? Check out the diagram below ... seems to contain and slowly rotate the K1 media ... only drawback i can think of is maybe some of the solid waste getting stuck on the k1 media ... but I would this that would come of with time moving around.

Thoughts ...

[ATTACH=CONFIG]5988[/ATTACH]

That design looks familiar. Great to see original content.......lol

Earthan Groups - DIY Pond and Fish Filter | Earthan Group Pty Ltd

Anyway, short answer would be not a great idea. The flow would be restriced in the centre and it would more than likely overflow the center "bucket" often. That filter works perfectly as it is without the media, I should know I designed it. Use it with a moving bed bio filter for further bio filtration (or just your media grow beds) or a separate packed media filter if you want to polish the water more before entering your grow bed.

Regards

Paul

[brendon 12]

Paul - Yes it should look familiar ... great design, but I was trying to save some space with the combination. Thanks for the input!

Brendon

[averan 21]

I just posted my design of a hybrid bio-radial flow filter here yesterday: http://www.aquaponicshq.com/forums/showthread.php?t=5457&p=57939&viewfull=1#post57939

Here's the link to the Sketchup model: http://sketchup.google.com/3dwarehouse/details?mid=f5100f3a4186ae7c26519479ab1f4b61&prevstart=0.

I've designed extra space/height into it to allow for some eventual flow reduction due to solids buildup over time. Draining off the solids and adding worms (and aeration?) should (in theory) keep it working. You can use any type of filter medium and it would be pretty easy to spray the inner walls of the mesh cylinder with a hose or backwash from above from time to time to remove excess solids.

[averan 21]

I forgot to mention, you do not want to fill the central column with media. That would restrict flow too much and ruin the solid settling and drainoff function. Instead, I insert some plastic mesh fencing to create a cylinder to hold media in the outer column where the water is returning upward after dropping heavier particles. Simply cut the plastic mesh so that it wraps around a 5 gal bucket, then zip tie it closed. It is an easier way to support the bucket up top.

[longnt 16]

The K1 needs a lot of oxygen to work effectively. With your design, K1 will move slowly. I suspect fish poo may clog it especially inside the K1. You may not have enough DO for bacteria to grow in the large surface of K1. If you put K1 out side then it also loses self cleaning ability.

I think you may save some money by using some kind of mesh like bird net and regularly take the net out and clean it with FT water.

To save the space, you may build a moving bed filter in you FT. The water near surface of FT has little solid waste and the air also aerate your FT too.

Cheers,

Long.

[GaryD 1053]

Hi Long,

Welcome to APHQ.

I invite you to peruse this thread. It will assist you to make the most effective use of APHQ.....and will connect you with my other web sites.

The K1 needs a lot of oxygen to work effectively.

K1 doesn't use oxygen as such....past that contained in the modest amount of air that creates the 'simmering' movement.

I've tried putting a moving bed bio-filter in the fish tank and I found that it affected the water dynamics in the fish tanks and hindered the removal of solids.

Similarly, I've incorporated a packed media filter within a swirl filter and, while it increased the system footprint, I found that a separate packed media filter worked better......while offering better access for cleaning both the swirl filter and the packed media filter.

While bird netting is much cheaper than K1, I've found that the enhanced filtration (or bio-filtration)....and easer cleaning.....justifies the added cost.

Regards.....Gary

[longnt 16]

Hi Gary,

Thank for sharing of your design of a combine filter. I may build one like your and put it inside my sum. I have saw system use K1 for MBR and trickle filter. These systems inherent high aeration in its design. I thought that K1 is expensive and bacteria need oxygen to work and grow up thus high DO level water is needed if we use K1 (some said 5-7mg/L).

K1 is expensive because it can self clean and high surface/volume. So I think if we have to clean it manually then the bird netting may be better as it is cheap and if compact high enough it will have higher surface/volume than K1 although it may restrict flow.

I have 2 sets of 90mm PVC with air stone inside in my IBC to move water up the surface from bottom of FT and don't have any problem with solid in my FT. The air stone itself can move water up if I put it on the bottom but the air flow will be reduced due to high pressure (I have that problem with an 4 outlets aquarium pump). So my air stone is set only about 10cm under water and it has a lot of air flow to suck water from bottom up through the PVC. That is why I think that if we put an MBR in FT high enough that bottom of MBR is far from FT bottom then we don't have much problem with solid clogging the K1.

Cheers,

Long.

[GaryD 1053]

Hi longt.

Thank for sharing of your design of a combine filter. I may build one like your and put it inside my sum. I have saw system use K1 for MBR and trickle filter. These systems inherent high aeration in its design. I thought that K1 is expensive and bacteria need oxygen to work and grow up thus high DO level water is needed if we use K1 (some said 5-7mg/L).

Since you use air to move the K1 (in a moving bed bio-filter), aeration of the system is an automatic consequence of the process. Similarly, if you used K1 in a trickling bio-filter, aeration is assured.

K1 is expensive because it can self clean and high surface/volume. So I think if we have to clean it manually then the bird netting may be better as it is cheap and if compact high enough it will have higher surface/volume than K1 although it may restrict flow.

The easiest way to clean K1 is to "boil" it with air.

I have 2 sets of 90mm PVC with air stone inside in my IBC to move water up the surface from bottom of FT and don't have any problem with solid in my FT.

What you've described is a simple airlift and, used this way, they are an excellent way to stir the fish tank water.

That is why I think that if we put an MBR in FT high enough that bottom of MBR is far from FT bottom then we don't have much problem with solid clogging the K1

The problem that I experienced with having an MBBR in the fish tank was more about the impact on the water movement within the tank than the media clogging.

Give it a go.....nothing ventured, nothing gained.

Gary

[ElevatedAquaponics 0]

While making my own bio-radial filter, I came up with the simple idea of using two 5 gallon buckets inside of each other; making it possible for water to rise from bottom through bio-media in upper bucket and over flow out.....ideas....comments? (Over-flow would be through both buckets)

[GaryD 1053]

Hi EA,

 

Welcome to Aquaponics Nation.

 

I'm struggling with visualising quite how your proposed bio-radial filter works.  Can you provide more detail.....or a drawing perhaps?

 

Gary

[averan 21]

Somewhat related, I fiddled with the design again, and combined a swirl filter with a radial flow filter. Am I just being silly or is this the best of both worlds?

[GaryD 1053]

Hi Averan,

 

Good to hear from you again.

 

In looking at your drawing, I can see where the water enters the unit through the 90^o bend in the LH side of the outer barrel.  Am I correct in assuming that the water (less the solids that gravitate to the bottom of the outer vessel) then passes through slots or holes in the side of the inner vessel......before exiting the filter through the weir in the centre of the inner vessel?

 

Gary

[averan 21]

Hey Gary,

 

The bottom of the 5 Gal bucket is cut out, totally open. Water swirls in around the outside and down, then turns inward and upward through the bottom of the bucket up to the weir/outlet. I have a cylinder of black plastic mesh fencing (curved back on itself) in there just to help support the bucket.

[kellenw 854]

Hi Averan,

 

Will your tank (trash can) be above ground or buried?  The reason I ask is that those rubber trash cans tend to flex a great deal when filled with water.  If it's above ground, you'll most likely need a support structure around it to prevent the flexing from compromising plumbing seals and so forth.

[averan 21]

I only recommend using the Brute line of cans from Rubbermaid. Above or below ground they can handle the weight of the water. The filter can just as easily be built with poly barrels.

[GaryD 1053]

Hi Averan,

 

The bottom of the 5 Gal bucket is cut out, totally open. Water swirls in around the outside and down, then turns inward and upward through the bottom of the bucket up to the weir/outlet. I have a cylinder of black plastic mesh fencing (curved back on itself) in there just to help support the bucket.

 

 

OK....so what would be the benefit of this arrangement over a conventional radial flow separator?

 

As an aside, if your bucket had a mesh base or (better still) was made completely of rigid mesh, you could fill it with something like K1 media and it would function as a packed media filter.  The whole thing would then work like a Nexus Eazy Pod filter.......like the one that I used on my Combo system.

 

Gary

 

[averan 21]

that is what i'm asking. what, if any, would be the benefit of swirl + radial flow? i can see the combo being better than just a swirl, but maybe a straight radial flow is better than the combo?

 

that filter you posted has the flow going the other way around by the looks of it. with mine, you can easily fill the outer volume with whatever you want, bird netting, K1, whatever. you just need to use the right size plastic fencing in the central column that holds the bucket up.

[ande 818]

that is what i'm asking. what, if any, would be the benefit of swirl + radial flow? i can see the combo being better than just a swirl, but maybe a straight radial flow is better than the combo?

 

Hi

I think a straight radial flow would be the best ? it beats swirl

http://www.w-m-t.com/library/pdf/Radial_Flow_Settler_Whitepaper.pdf

The combo only complicate the building/making of the solids separator IMO keep it KISS in DIY

 

that filter you posted has the flow going the other way around by the looks of it.

Here is how it woorks

 

http://www.evolutionaqua.com/acatalog/Eazy_Pod_Installation_Brochure.pdf

 

cheers

Edited January 5, 2014 by ande (see edit history)

[ande 818]

I just posted my design of a hybrid bio-radial flow filter here yesterday: http://www.aquaponicshq.com/forums/showthread.php?t=5457&p=57939&viewfull=1#post57939

 

Don't know why your link dosen't work ? but I belive it was to this post ? http://aquaponicsnation.com/forums/topic/5279-solids-separators/?p=56147

 

cheers

[GaryD 1053]

HI Averan,

 

that is what i'm asking. what, if any, would be the benefit of swirl + radial flow? i can see the combo being better than just a swirl, but maybe a straight radial flow is better than the combo?

 

I agree with Ande…..the straight radial flow filter is the way to go.  It's much more efficient than a standard swirl filter.

 

The Nexus filter that I used in my Combo system is a combination swirl and packed media filter.  I think your question is a reasonable one……and I think that a straight radial flow filter is probably better for capturing sedimentary solids than a Nexus Eazy Pod.  Where it closes the gap is that it also traps suspended solids.

 

Like any combination device, it represents a compromise.   I've built lots of combination filters and, for my money, I prefer dedicated devices……largely for the fact that they are usually more efficient - and are generally much easier to clean.

 

To summarise, I'd opt for a radial flow separator and a packed media filter…….in two separate barrels.  In an ideal world, I'd have a sieve filter upstream of the radial flow separator.

 

 

Gary