Welcome to Koi Forum. Is this your first visit? Register
Results 1 to 20 of 20
  1. #1

    Pump head height flow ?

    When manufactures of submersible pond pumps say for example that this pump has a flow rate of 1000lph at 2m head height does this mean 2m from the pump at the bottom of the pond or 2m above water level? Struggling to find info on it cheers guys.


    Sent from my iPhone using Tapatalk



  2. Thanks freddyboy Thanked / Liked this Post
  3. #2
    2m above the pump I think

  4. Thanks freddyboy Thanked / Liked this Post
  5. #3
    Senior Member Rank = Yonsai Simon Fish's Avatar
    Join Date
    Nov 2018
    Location
    Nottingham
    Posts
    226
    Thanks / Likes
    310
    Its above the water level.
    Think about it if you had a 7 ft deep pond and a 6ft head pump, would it not work?

  6. Thanks freddyboy Thanked / Liked this Post
  7. #4
    Quote Originally Posted by Simon Fish View Post
    Its above the water level.
    Think about it if you had a 7 ft deep pond and a 6ft head pump, would it not work?
    I donít know mate thatís why Iím asking Pump head height flow ?


    Sent from my iPhone using Tapatalk

  8. Thanks freddyboy Thanked / Liked this Post
  9. #5
    Senior Member Rank = Yonsai Simon Fish's Avatar
    Join Date
    Nov 2018
    Location
    Nottingham
    Posts
    226
    Thanks / Likes
    310
    Quote Originally Posted by charco123 View Post
    I don’t know mate that’s why I’m asking Pump head height flow ?


    Sent from my iPhone using Tapatalk
    It would work.
    The head height equates to pressure,
    so head of 2m is 0.2 bar pressure.
    This means it will lift to that level, but the flow will decrease as the height is raised.

  10. Thanks freddyboy Thanked / Liked this Post
  11. #6
    Senior Member Rank = Supreme Champion freddyboy's Avatar
    Join Date
    Mar 2016
    Posts
    8,253
    Thanks / Likes
    12492
    Quote Originally Posted by charco123 View Post
    When manufactures of submersible pond pumps say for example that this pump has a flow rate of 1000lph at 2m head height does this mean 2m from the pump at the bottom of the pond or 2m above water level? Struggling to find info on it cheers guys.


    Sent from my iPhone using Tapatalk
    Good questions charles

    Sent from my SM-G960F using Tapatalk

  12. Thanks Ajm Thanked / Liked this Post
  13. #7
    Quote Originally Posted by Simon Fish View Post
    It would work.
    The head height equates to pressure,
    so head of 2m is 0.2 bar pressure.
    This means it will lift to that level, but the flow will decrease as the height is raised.
    Cheers Simon read and understoodPump head height flow ?


    Sent from my iPhone using Tapatalk

  14. #8
    Quote Originally Posted by charco123 View Post
    When manufactures of submersible pond pumps say for example that this pump has a flow rate of 1000lph at 2m head height does this mean 2m from the pump at the bottom of the pond or 2m above water level? Struggling to find info on it cheers guys.

    Sent from my iPhone using Tapatalk
    It means 2 meters above the water level in the pond.

    Strictly, you have to subtract from the 1,000 lph flow rate, any friction loss caused by the pipework but, in practice, this is unlikely to be great if you don't have a long pipe with several fittings.

  15. Thanks Ajm, Frimley Koi keeper, freddyboy, Gazkoi, charco123 Thanked / Liked this Post
  16. #9
    I'm with DJ on this as I think it's from the pump.

    The way to prove it is sit the pump in a tub of water with a 3m hose attached to it and see how high you can lift the pipe before the flow rate starts to drop off. Or sit the pump in the pond and do the same thing. if the pond is 2m deep and you can only lift the end of the pipe just above the surface of the pond before you loose flow then it's from the pump if not then it's from the surface of the water.

    Yes I realise a 3m pipe will only give you 1m above the surface of the water if the water is 2m deep but you get the idea and you could even raise the pump so it's only 1m down and see what happens?

    The other thing to consider is, is it a 2m vertical lift or a 2m lift of any sort?

    Don't forget that the length of run also affects the flow rate so most pumps are rated for a height they will lift and a length they will push through as well I think you will find?

    Also if the pipework lifts and then drops, does the drop then help with the flow rate as in gravity starts to pull (not the right term I know) the water back down again or do you start to get a siphoning effect? Does the siphoning effect only work if the end of the pipe is lower than the pump? Sorry my knowledge of physics is a bit limited.

    Apparently it is not possible to pull water, you can only actually push it as it isn't solid enough. Well that's how it was explained to me by someone with a better understanding of physics and water dynamics.

    Basically the way I see it is if the max head rating of any pump is from the surface of the water it does make sense as the pump could then be sitting at say 10m below the surface and then still be able to pump its max head rating, then a 2m rating then becomes 12m?

  17. Thanks Ajm, charco123 Thanked / Liked this Post
  18. #10
    OK I stand corrected.

    Sorry I didn't see your reply until I refreshed the web page after replying Syd.

  19. Thanks Ajm, Manky Sanke, freddyboy, charco123 Thanked / Liked this Post
  20. #11
    Quote Originally Posted by Manky Sanke View Post
    It means 2 meters above the water level in the pond.

    Strictly, you have to subtract from the 1,000 lph flow rate, any friction loss caused by the pipework but, in practice, this is unlikely to be great if you don't have a long pipe with several fittings.
    Lovely cheers mate appreciate it ! Pump head height flow ?


    Sent from my iPhone using Tapatalk

  21. Thanks freddyboy, Frimley Koi keeper Thanked / Liked this Post
  22. #12
    OK so I may have been wrong but I made a good argument for my reasoning didn't I

  23. Thanks Ajm, freddyboy, john1 Thanked / Liked this Post
  24. #13
    Extreme Koi Member Rank = Supreme Champion john1's Avatar
    Join Date
    Aug 2013
    Location
    N.Wales.
    Posts
    5,497
    Thanks / Likes
    9286
    Welcome back Frim, you been busy with the q/t all this while ?
    John

  25. Thanks Frimley Koi keeper, Ajm, freddyboy Thanked / Liked this Post
  26. #14
    Thanks John.

    I've been thinking about it lol problem now is that the girlfriend is working from home so I can't do anything as she still doesn't know about it

  27. Thanks john1, freddyboy Thanked / Liked this Post
  28. #15
    Senior Member Rank = Grand Champion Ajm's Avatar
    Join Date
    Mar 2018
    Location
    Durham
    Posts
    3,396
    Thanks / Likes
    7347
    Quote Originally Posted by Frimley Koi keeper View Post
    Thanks John.

    I've been thinking about it lol problem now is that the girlfriend is working from home so I can't do anything as she still doesn't know about it
    More excuses haha

    Sent from my SM-G973F using Tapatalk
    Johnathan

  29. Thanks john1, Frimley Koi keeper, freddyboy Thanked / Liked this Post
  30. #16
    Extreme Koi Member Rank = Supreme Champion john1's Avatar
    Join Date
    Aug 2013
    Location
    N.Wales.
    Posts
    5,497
    Thanks / Likes
    9286
    Just come clean Frim,she may rant a bit but she will come round,just say would you rather me be in the pub and at least you are at home doing the q/t.
    John

  31. Thanks Ajm, Frimley Koi keeper, freddyboy Thanked / Liked this Post
  32. #17
    Senior Member Rank = Grand Champion Ajm's Avatar
    Join Date
    Mar 2018
    Location
    Durham
    Posts
    3,396
    Thanks / Likes
    7347
    Haha johns right . Man up and say look love am having a qt it's getting done if ya dont like it get in the spare room

    Sent from my SM-G973F using Tapatalk
    Johnathan

  33. Thanks john1, Frimley Koi keeper, freddyboy Thanked / Liked this Post
  34. #18
    Quote Originally Posted by john1 View Post
    Just come clean Frim,she may rant a bit but she will come round,just say would you rather me be in the pub and at least you are at home doing the q/t.
    She may rant a bit !!! That's an understatement

  35. Thanks Ajm, freddyboy, john1 Thanked / Liked this Post
  36. #19
    Senior Member Rank = Supreme Champion freddyboy's Avatar
    Join Date
    Mar 2016
    Posts
    8,253
    Thanks / Likes
    12492
    Quote Originally Posted by Frimley Koi keeper View Post
    Thanks John.

    I've been thinking about it lol problem now is that the girlfriend is working from home so I can't do anything as she still doesn't know about it
    Haha Pump head height flow ?Pump head height flow ? why don t you tell her it's a hot tub lol

    Sent from my SM-G960F using Tapatalk

  37. Thanks Frimley Koi keeper, Ajm, john1 Thanked / Liked this Post
  38. #20
    Senior Member Rank = Yonsai RipleyRich's Avatar
    Join Date
    Feb 2017
    Location
    Ripley, Derbyshire
    Posts
    187
    Thanks / Likes
    176
    2m head is the equivalent resistance it is measured against.

    Every length of pipe and fitting adds resistance to the pump and reduces flow.
    Resistance is measured in various equivalent units, m Head, Pascals, bar etc.

    The best way to understand it is this.
    If you fill a bucket from your outside tap it takes maybe 10 seconds to fill.
    Now attach your 25m hosepipe and fill it. It may take 30 seconds.
    Thats because of the frictional losses (Head loss) caused by the hosepipe and ultimately the flow rate into the bucket is reduced.

    The smaller the pipe - the greater the losses.
    The longer the pipe - the greater the losses.
    The more fittings - the greater the losses.

    My filter is recommended for a maximum flow of 12500 litres. I run a 15000 litre pump (15000 litres @2m head) and I am certain an 18000 or even 20000 would be fine due to pipe losses, valves, UV etc.

  39. Thanks freddyboy, Frimley Koi keeper, Ajm Thanked / Liked this Post
 

 

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
All times are GMT +1. The time now is 10:22 AM. Online Koi Mag Forum
Powered by vBulletin® Version 4.2.3
Copyright © 2020 vBulletin Solutions, Inc. All rights reserved.

vBulletin Improved By vBFoster® (Lite Version), © UltimateScheme, Ltd.