Is a biofilter supposed to be outside the pond?

Discussion in 'DIY - Do It Yourself' started by Lumka, Jan 9, 2017.

  1. Lumka

    Lumka

    Joined:
    Oct 22, 2014
    Messages:
    7
    Hi, I have a 1300 gallon pond, and I am planning to build a DIY biofilter. As I am searching the net - it seems that in all the designs the filter is outside the pond. Is there a reason for this? My plan is [was] to make a submersible filter, but now I have my doubts. Can someone please be so kind as to tell me what is wrong with my logic?

    What I plan is a tote box, sitting on the bottom, connected to my pump. Forgive my hand drawn diagram! I have a 2000g/h pump, and was planning to line the tote with filter sponges --> bioballs --> carbon.

    [​IMG]

    The reason I have for making it submersible is to hide the setup, and not have an eyesore outside.

    I would like any suggestions, please.
     
    Lumka, Jan 9, 2017
    #1
    Tula likes this.
    1. Advertisements

  2. Lumka

    Tula

    Joined:
    Sep 14, 2013
    Messages:
    2,481
    Location:
    Cincinnati, Ohio
    My first pond had a similar type filter, an all in one box that rested on the bottom of the pond. It seemed to work ok, but it was not easy to remove and clean.

    I believe one reason the bio filters you see on line, are often outside the pond, is they require the presence of air. Lots of people make baki type showers and use them as water falls.
     
    Tula, Jan 10, 2017
    #2
    Mmathis likes this.
    1. Advertisements

  3. Lumka

    Mmathis TurtleMommy

    Joined:
    Apr 28, 2011
    Messages:
    7,508
    Location:
    NW Louisiana -- zone 8b
    Like @Tula said, ease of cleaning and introduction of air.
     
    Mmathis, Jan 10, 2017
    #3
    Meyer Jordan likes this.
  4. Lumka

    Meyer Jordan Tadpole

    Joined:
    Oct 10, 2014
    Messages:
    5,093
    Location:
    Pensacola, Florida
    In addition to what has already be said, your biofilter design in itself does not allow for ease of maintenance. Activated Carbon in a biofilter can be quite beneficial in removing certain pollutants but effective lifespan is, at the most, a few weeks. At which time it will need to be completely replaced. Not easily done with your design.
     
    Meyer Jordan, Jan 10, 2017
    #4
  5. Lumka

    morewater President, Raccoon Haters International

    Joined:
    Feb 18, 2014
    Messages:
    1,329
    Location:
    York Region, Ontario
    A tote box will weigh quite a bit when it is filled with soaked sponges and soaked carbon. Lifting this box out of the water in order to clean it will most likely result in it "bending" and spilling the contents out into the pond, thereby re-releasing the contaminants that you so diligently "collected" back into the water column.

    Any above-ground, below-ground or hybrid bio-filter construction needs to be of rigid material, be easy to drain and clean.

    Barrel bio-filters (40gal, 55gal) can easily be dug into the existing landscape to reduce their visual presence and can quite easily be disguised with stone and plant materials while still being relatively easy to service.

    Sponges, while they may work are an absolute pain-in-the-posterior to clean as they each have to be cleaned individually and tend to re-clog rather quickly. You're better off with a hard substrate such as bio-balls or some such other easily-cleaned material. Lava rock is in the same category, it's heavy, clogs up quickly and isn't easy to clean.

    Matala mats (when used in successively decreasing pore sizes) will trap the vast majority of the suspended detritus. Furnace filters, floor scrubbing pads, etc. are either too fine a mesh or too large a mesh. Do it once and do it right.

    If you're going to go the barrel route, ensure that the barrel is of "food grade" material meaning that it wasn't used originally to transport solvents, etc.

    A final thought, a "bottom up" design is more efficient than a "flow through" design. Gravity is your friend.
     
    morewater, Jan 10, 2017
    #5
    CeeJayH, MitchM, Tula and 2 others like this.
  6. Lumka

    Lumka

    Joined:
    Oct 22, 2014
    Messages:
    7
    Thanks all for the feedback! I especially like the comment: do it once and do it right. Appreciate it!
     
    Lumka, Jan 11, 2017
    #6
  7. Lumka

    Usman

    Joined:
    May 26, 2014
    Messages:
    389
    welcome , use gravel if u want thats best underwater filter since water will go thru it easily and will not get clogged for long time as used in aquariums and you dont need to take it out to clean it , sponges are used mostly where it can be easily cleaned since its mesh is finer and will catch even the finest debris , it wil get blocked too quick to pass water properly
    i have read some where bio filter needs to be near the surface within a 10 inches to function at its fullest , may be u can place some hollow blocks below and raise it like a bog inside pond corner , i have seen submersible filters for polishing water as you want but they are made on smaller scale like in buckets that can be taken out
     
    Usman, Jan 17, 2017
    #7
    Lumka likes this.
  8. Lumka

    budgenator

    Joined:
    Jul 12, 2016
    Messages:
    158
    Location:
    Croswell MI
    In pond bio-filters work okay, but they are a PITA to maintain! Every weekend you have to pull them out and wash out the foam, and it just kills your weekend. I gave up on them when I realised I was seriously contemplating building a crane attachment for my lawn tractor to pull those heavy things out of the water.
    Now everything I do is measured against 1. is it easier and 2. is it better. I know if it isn't easier, I'll put it off so it doesn't matter if it's better. I'd love to get my weekly pond maintenance down to 20 or 30 minutes, more time for enjoying the pond.
    At 1300 gallon pond, you're going to want 130 gallons of filtration, by adding plants you can cut back the filtration a bit, Goldfish don't need as much filtration as Koi do also.
     
    budgenator, Jan 23, 2017
    #8
    Lumka likes this.
  9. Lumka

    Meyer Jordan Tadpole

    Joined:
    Oct 10, 2014
    Messages:
    5,093
    Location:
    Pensacola, Florida
    How do you arrive at this figure?
     
    Meyer Jordan, Jan 24, 2017
    #9
  10. Lumka

    budgenator

    Joined:
    Jul 12, 2016
    Messages:
    158
    Location:
    Croswell MI
    I assumed it was a widely recognised rule of thumb, http://www.koiphen.com/forums/showthread.php?127398-Pond-and-construction-forum-101
    http://www.matalausa.com/How-Much-Matala/How-Much-Matala-Will-You-Need-p-68.html
    it's overkill if your using Matala and a K1 MBBR but he's talking sponge pre-filter and bioballs and AC all in one tote filter.

    In fact Lumka, look into getting green Matala or even better green and blue http://www.matalausa.com/Matala-Filter-Media-Info-c-26.html to use instead of the sponge filter, you'll be much happier with it. If matala is out of your budget range, you can still design to use a 1/4 sheet of matala sized filter, and locate a sponge the same size so it's easier to upgrade later when your fish get bigger.
     
    budgenator, Jan 24, 2017
    #10
  11. Lumka

    Meyer Jordan Tadpole

    Joined:
    Oct 10, 2014
    Messages:
    5,093
    Location:
    Pensacola, Florida
    Using rules of thumb can be dangerous because they usually have no basis in fact and may result in the "thumb" being in your eye or stuck up some other unmentionable location. They are entirely too vague. I am especially leery when the author can not even spell-
    • 10 % pond volume in filteration (sic) volume
    • 1/3 of total surface area of pond = surface area needed for fliteration (sic).
    (From the Koiphen link).

    And even though it is reasonable to assume that Matala knows what the SSA is of their pads, even they are vague in the use of terms like light. medium and heavy fish loads. These terms are subjective and open to individual interpretation.
     
    Meyer Jordan, Jan 24, 2017
    #11
  12. Lumka

    Gordo33

    Joined:
    Nov 16, 2015
    Messages:
    170
    Location:
    Willow Grove,PA
    What rule do you follow for determining the amount of filtration necessary for a goldfish or a koi pond? When I built my goldfish pond I was advised by several members of a pond forum to use the 10% of pond volume as a general rule. It seems that's a consistent consensus from multiple sites. To date it has worked keeping the water clear and all water test results where they need to be. I am considering adding a koi pond this year and am interested to here your thoughts.
     
    Gordo33, Jan 25, 2017
    #12
  13. Lumka

    Meyer Jordan Tadpole

    Joined:
    Oct 10, 2014
    Messages:
    5,093
    Location:
    Pensacola, Florida
    I will cede the fact that if, indeed, one was to follow the 10% capacity rule they would probably not encounter any problems, but the real question is how many pond owners really follow this rule. For a pond with a capacity of 1000 gallons this means that the biofilter must, according to the rule, have a capacity of 100 gallons. I can truthfully say that I don't believe that there is a commercially manufactured biofilter presently available that has a capacity of 100 gallons that is logically affordable for a 1000 gallon pond.. I seriously doubt that any pondkeeper is going to spend more on the biofilter module than they did on the entire rest of the pond including the fish and plants. But if they do, I grant you that they would have enough SSA to support quite a number of fish.
    This, of course, does not include "bogs".
     
    Meyer Jordan, Jan 25, 2017
    #13
  14. Lumka

    Gordo33

    Joined:
    Nov 16, 2015
    Messages:
    170
    Location:
    Willow Grove,PA
    Agree with the expense but a 100 gal Rubbermaid tank cost me $95. Stocked with yellow flag iris and 50# lava rock in a laundry bag wrapped in quilt batting to prevent clogging added approx $25. Plumbing approx $50. Plus an 8 foot long x 4 wide stream planted cost $25. Grand total $195. DIY affordable and so far very affective.
    So are you saying commercial available biofilters that are affordable would hold a smaller volume of water. How do you determine the proper size biofilter ? What makes one biofilter better than another?
     
    Gordo33, Jan 25, 2017
    #14
  15. Lumka

    Meyer Jordan Tadpole

    Joined:
    Oct 10, 2014
    Messages:
    5,093
    Location:
    Pensacola, Florida
    One method for determining the minimum required level of biofiltration is determined by total fish mass. Ideally, future fish mass should be the guideline as fish will grow over time. Another method advocates using the amount of feed offered daily as the base line, but, although this will give a more conservative result, it does not account for fish producing Ammonia through respiration EVEN during a prolonged state of fasting.
    To cover one's tracks, so to speak, I would advise using both methods and use the result that indicates the higher required SSA for complete Ammonia conversion.

    The fish mass only method is generally described at this link-
    http://www.russellwatergardens.com/calculations/how-many-fish-can-i-have-in-my-pond/

    The feed method is described in this document-
     

    Attached Files:

    Last edited: Jan 26, 2017
    Meyer Jordan, Jan 26, 2017
    #15
    Becky likes this.
  16. Lumka

    Meyer Jordan Tadpole

    Joined:
    Oct 10, 2014
    Messages:
    5,093
    Location:
    Pensacola, Florida
    Assuming that all equally convert the same amount of Ammonia, then I would think that ease of maintenance and possibly total footprint could be deciding factors.
     
    Meyer Jordan, Jan 26, 2017
    #16
  17. Lumka

    Koi4JT

    Joined:
    Aug 21, 2016
    Messages:
    10
    Location:
    Western Henrico County (Richmond) Virginia
    When I first built my pond, similar size to yours, I built my own above ground bio-filter. It worked great but was a weekly nightmare to clean. When I decided to expand my pond by 50%, the new pond area blocked where my bio-filter was located, so I did some research and chose to build a "bog", essentially another pond (60"W x 24"L x 48"D) filled with pea gravel. It works incredibly well, the ponds require no maintenance, and once every couple of years or so I backwash the bog. As far as i am concerned, the bog is the best way to go and I grow plants in the top so it looks quite natural.
     
    Koi4JT, Feb 1, 2017
    #17
    Usman likes this.
  18. Lumka

    barryian

    Joined:
    Sep 3, 2013
    Messages:
    494
    Location:
    Long Island, NY
    Did notice that spelling also!
     
    barryian, Feb 2, 2017
    #18
  19. Lumka

    Waterbug

    Joined:
    Apr 10, 2010
    Messages:
    3,026
    Location:
    Phoenix AZ
    Carbon would be a mechanical filter element.I personally don't care for combo filters. Mechanical is a whole deal I won't get into here.

    For bio above ground has been proven much more efficient, like 10x or more. The increased O2 makes bacteria happier and also above ground keeps the bacteria cleaner which means it can get to O2 and other chemicals in the water. These are also easier and cheaper to build than virtually all submerged filters and virtually never need to be cleaned. This also makes them steady at removing ammonia while a submerged will decrease in performance as it clogs. I think a case could be made for submerged bio filters not working at all. Keep in mind the entire pond, the pipes/hose, are a bio filter. Google "Trickle Tower" and "Shower filter" for more info. Most will be large, but they can be scaled to very small.

    High fish load ponds need bio filters. Virtually all water gardens do not need any. Because of that it doesn't normally matter whether submerged or not. Lot's of people with submerged filters think the world of them, and give no credit to the bacteria on the pond walls or the algae which is doing virtually all bio filtering. For many people, especially in the high end, it seems like the water and fish are just an excuse for have large, complex, expensive filters. The filters ARE the hobby.

    Rules of thumb on filter size can seem pretty silly the more you learn. A filter that's 10x more efficient certainly should be a factor seems to me. The amount of fish by weight certainly key too. Amount of food being fed also, and that's normally related to fish size. Feeding fish 12 times a day with an auto feeder vs a couple times on the weekend makes a difference. Using pond volume as a factor never made any sense to me, but yeah, see it a lot online. Same for pump size.

    Bottom line is keeping a pond is a hobby so you should do what makes you happy. There's no right or wrong as long as you're having fun. Making submerged filters is a lot of fun...not sure why.I sure used to enjoy it.
     
    Waterbug, Feb 7, 2017
    #19
    makuck and Usman like this.
  20. Lumka

    makuck

    Joined:
    Feb 9, 2017
    Messages:
    7
    Location:
    Northwest Mountains of Colorado
    I would ditto what Waterbug said.

    My take on this is based on large aquariums which usually require intensive filtration I have managed to get away with no filter changes on medium-density tanks:

    I always go with planted bottoms. Planted bottom tanks and ponds are great, plants are a great oxygenator and take up excess nutrients/excrement.

    In my experience, with planted tanks: if you have just a ton of lava rock, polyester fill (like for blankets or pillows found at wall mart cheap), plastic scrubby pads you can just stack those things up and run water through them and good bacteria will grow like crazy, you will never ever have to replace any of it, if you have enough surface area. The surface area is key. More surface area means more oxygen. Even just pumping water up and dropping it down aerates it. The key is moving the water oxygenates it. Air bubblers are good. If you can make a small stream or waterfall all the more balancing that will be to the small pond. Air is an input but a really cheap one and can really help get the beneficial bacteria, plants & algae started, and it's essential for any fish, as important as the filter. Size trumps almost any problem with the filter. Overbuild it and force the water through as much of it as possible. I like to do tiers and drill holes so the water rains down through each level of filtration. A couple 5-gallon buckets filled with media would probably work. If you wanted to go all-out a 30-55G drum. The bigger your filter is the less algae growth and ammonia spikes etc there will be. Big surface area of biological action = good no matter how you cut it.
     
    makuck, Feb 9, 2017
    #20
    1. Advertisements

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. koiguy1969

    pruning lillies from outside the pond??

    koiguy1969, Jun 13, 2009, in forum: Aquatic Plants
    Replies:
    10
    Views:
    1,664
    MassKoi
    Jun 15, 2009
  2. JanScearce

    When to return Koi to outside pond in Indiana

    JanScearce, Apr 10, 2011, in forum: Newbies to Garden Ponds
    Replies:
    3
    Views:
    1,670
    RSFish1
    Apr 12, 2011
  3. deadringer303
    Replies:
    6
    Views:
    1,308
    Waterbug
    May 2, 2012
  4. Sharon Goode

    Whats my next step for winterizing outside pond

    Sharon Goode, Nov 8, 2013, in forum: Newbies to Garden Ponds
    Replies:
    14
    Views:
    813
    Tanya
    Dec 3, 2013
  5. Priscilla

    Been busy outside the pond

    Priscilla, Sep 10, 2015, in forum: General Chat
    Replies:
    10
    Views:
    380
    bettasngoldfish
    Sep 11, 2015
Loading...