Increasing the flow in a dsb

Discussion in 'Biological/Natural Filtration and Deep Sand Beds' started by frankie fish, 20 Jul 2010.

  1. frankie fish

    frankie fish

    Joined:
    21 Jul 2009
    Posts:
    445
    Likes Received:
    0
    Location:
    vereeniging
    Just a quick question,how do i safely increase the flow in my dsb without increasing the return pumps capacity,coz currently i'm running 2*3000l/h pumps=6000l without headloss,how do i calculate that anyway,water being pumped up straight 4 about 1.6m,in a 25mm tube. Any help?pls
     
  2. AdS Guest




    to hide all adverts.
  3. Tobes

    Tobes Retired Moderator

    Joined:
    30 Nov 2007
    Posts:
    9,482
    Likes Received:
    118
    Location:
    A Beautiful place!
    Why would you wanna increase the flow? Running only 1 x 3000lph pump should be fine. If the water goes over the DSB too quickly it won't work.
    The water needs to siphon a bit lower into the sand for the denitrification to take place. Also, your skimmer will be less effective if the water just rushes past it.
    Posted via Mobile Device
     
  4. frankie fish

    frankie fish Thread Starter

    Joined:
    21 Jul 2009
    Posts:
    445
    Likes Received:
    0
    Location:
    vereeniging
    It just seems a bit slow,cyno forms on the dsb surface,and the culerpa in the dsb r not even moving. How do i calculate the current flow?
     
  5. RiaanP

    RiaanP Moderator

    Joined:
    11 Aug 2008
    Posts:
    23,165
    Likes Received:
    1,232
    Location:
    Centurion
    Check on the box the pump came with, There should be a graph of water delivery at different heights. But that exludes any elbows and sharp corners.
     
  6. RiaanP

    RiaanP Moderator

    Joined:
    11 Aug 2008
    Posts:
    23,165
    Likes Received:
    1,232
    Location:
    Centurion
    Or, if you really want to up the flow in the DSB, just use another small pump, like 500L depending on volume you want extra. Put it in the return chamber, with flexible hose going back to first chamber directly. That will increase the flow, without increasing throughput. Because of no head pressure due to lift or elbows, you should get 100% capacity of the pump delivered.
     
  7. jacquesb

    jacquesb Retired Moderator

    Joined:
    29 May 2007
    Posts:
    17,868
    Likes Received:
    69
    Location:
    Cape Town
    Something must be wrong with your DSB design, Frankie Fish, if you have 2 x 3000 liter per hour return pumps ALREADY, and the water is STILL not moving over your DSB at all?

    I have a 1500 liter total volume system, and my return pump is ONE x 2500 liter per hour.... This limited by my skimmer throughput at the moment, because my overflow goes directly into my external skimmer, and the skimmer is is supplying water to my sump.....

    Can you please post some clear detailed photo's of your sump for us?
     
  8. frankie fish

    frankie fish Thread Starter

    Joined:
    21 Jul 2009
    Posts:
    445
    Likes Received:
    0
    Location:
    vereeniging
    So last night i took some pics,and i also worked out a estimated flow of water. I have a est. 860l of water flowing into my sump, my tank's dimensions are 1.8*600*700,of which water level is 600,i also have about 40kg rock (of which 10kg is baserock),and i have a 2cm layer of sand for substrate. Lately i am having GHA problems,mainly due to my own neglect,and changing the substrate from crushed coral to sand(which i did too fast). i tested the water at my nearest lfs, die visdam, the first test i've done i saw some ammonia,nitrite and very high nitrate 50mg/100l. Second test,no ammonia,no nitrite,still nitrate is very high,50mg/100l. Which it boils down to is,that when i started my dsb,i used reggies playsand,about 15cm deep. i seeded it,but no discolouration in the bottom layers. I removed some sand from the bottom,and guess what,the sand was a bit on the dry side, which led me to the conclusion that very fine sand in a deep layer do not allow for water penetration in the botton layers, as i found only the top 5-8cm was wet. The sand in my DT,are showing lots of bubbles beneath the surface,unlike my dsb. any comment on this,coz i'm a little puzzled,thiking of starting a dsb from scratch,with the addition of a ATS,which is 90% complete. Here's a few pics,just struggling to upload
     
  9. frankie fish

    frankie fish Thread Starter

    Joined:
    21 Jul 2009
    Posts:
    445
    Likes Received:
    0
    Location:
    vereeniging
    [​IMG]

    [​IMG]
     
  10. frankie fish

    frankie fish Thread Starter

    Joined:
    21 Jul 2009
    Posts:
    445
    Likes Received:
    0
    Location:
    vereeniging
    [​IMG]
    Skimmer and skimate
    [​IMG]
    notice the almost non-existing flow
     
  11. frankie fish

    frankie fish Thread Starter

    Joined:
    21 Jul 2009
    Posts:
    445
    Likes Received:
    0
    Location:
    vereeniging
    [​IMG]
    The GHA on my rear pane, i clean it weekly,and every 2nd day on the rocks.
     
  12. mariusmeyer

    mariusmeyer

    Joined:
    7 Jul 2009
    Posts:
    3,055
    Likes Received:
    210
    Location:
    Jukskei Park, JHB
    2 3000LPH pumps as return and you are only getting 860L over the DSB? How did you get to the 860LPH? What is your phosphate readings as this together with the high nitrate will make it heaven for algae.
     
  13. jacquesb

    jacquesb Retired Moderator

    Joined:
    29 May 2007
    Posts:
    17,868
    Likes Received:
    69
    Location:
    Cape Town
    Good morning Frankie -

    OK - just to clarify things - it is not the water flow over the DSB, that ensures that water goes to the bottom-most areas of the DSB sand bed.....
    It's the working of the micro fauna..... ie, worms, pods, etc.....

    So - as you are saying - it seems that your DSB was never populated with pods.... Therefor, the DSB itself could never have been populated with bacteria, and therefor you have high nitrates......

    The +-870 liter per hour water flow through your sump, is not the culprit, though.....



     
  14. frankie fish

    frankie fish Thread Starter

    Joined:
    21 Jul 2009
    Posts:
    445
    Likes Received:
    0
    Location:
    vereeniging
    Beats me, i used a jug,and a timer,timed how many litre jugs i can fill in a minute,and multiplied that by 60
     
  15. frankie fish

    frankie fish Thread Starter

    Joined:
    21 Jul 2009
    Posts:
    445
    Likes Received:
    0
    Location:
    vereeniging
    I have some pods,not very much,but i have a few running around. I just mentioned the dry sand issue,coz that worries me,it's like the water does not reach the bottom layer of the dsb,coz the sand is too dense,thus causing the dsb not to work,just my assumption
     
  16. frankie fish

    frankie fish Thread Starter

    Joined:
    21 Jul 2009
    Posts:
    445
    Likes Received:
    0
    Location:
    vereeniging
    The nitrates is a mistake on my side,changing substrate too quickly, also a diy denitrator(which produced more nitrites,i tested the water from the outlet,and the nitrite reading was higher that the DT's water)
     
  17. jacquesb

    jacquesb Retired Moderator

    Joined:
    29 May 2007
    Posts:
    17,868
    Likes Received:
    69
    Location:
    Cape Town
    Hi Frankie - I have had my DSB 15cm deep/thick as well, also using playsand - and the water flow over my DSB/s was always +-1000 liters per hour. The worms dig little wormholes into the sand, all the way to the bottom.... and their "vibrations" and movement, always moves water to the bottom regions of my DSB's.....

    Perhaps try and get some more samples of DSB's from other reefkeepers, and perhaps also some chaetomorpha from different sources.... this SHOULD contain enough pods/worms to "kick-start" your DSB as well.

    In the interim, please dose bacteria additive, ie. Prodibio, etc.... to try and alleviate your ammonia/nitrite/nitrate problems - this will also have in "kick-starting" the bacteria in your DSB.....
     
  18. Allen

    Allen

    Joined:
    15 Nov 2008
    Posts:
    147
    Likes Received:
    0
    Location:
    Dar es Salaam, Tanzania
    Tagging
     
  19. AfricaOffroad

    AfricaOffroad

    Joined:
    12 Mar 2010
    Posts:
    1,696
    Likes Received:
    35
    Location:
    Ballito, KZN
    Frankie, check you pumps, they are operating way below their design capacities.
    Perhaps the impellors have missing veins?
     
Recent Posts

Loading...
Similar Threads - Increasing flow Forum Date
Increasing existing sump volume Beginner Discussions 14 Oct 2014
Increasing the pod population in my tank General Discussions and Advice 12 Jan 2014
increasing nitrates to get rid of phosphates? General Discussions and Advice 24 Sep 2013
Increasing Water Volume. Biological/Natural Filtration and Deep Sand Beds 3 Nov 2011
Increasing Phosphates Water Parameters and Additives 8 Dec 2010
Increasing Salinity Beginner Discussions 6 May 2008
Increasing/Decreasing PH Beginner Discussions 28 Apr 2008