Pump question.

[Daniel McElhattan]

When you are accounting for the vertical rise of water from your pump do you include distance traveled upward through water?  For instance Say my pump is at the bottom of a 3' tank and I go up another 2' from there.  Does that count as 2' or 5' when calculating your flow rate?

[TCLynx]

Head is figured from the surface of the water that the pump is pumping from.  So if your pump is drawing water from the bottom of a 3' deep tank and the grow bed surface is 2' above the surface of the water then you are only pumping to a head of about 2'.  Always figure a bit extra though and remember that when the water level in the fish tank or sump tank falls, the head increases.

[Daniel McElhattan]

Thanks for the answer. I figured the pressure of the water around would help push it those first 3'.  But its good to hear someone agree.

TCLynx said:

Head is figured from the surface of the water that the pump is pumping from.  So if your pump is drawing water from the bottom of a 3' deep tank and the grow bed surface is 2' above the surface of the water then you are only pumping to a head of about 2'.  Always figure a bit extra though and remember that when the water level in the fish tank or sump tank falls, the head increases.

[Paul Smith]

Hello. Can You help me with choosing how many litres or gallons my pump

choice should be with a CHOP 2.  4 IBC grow beds, Fish tank 1135 litres. sump tank 500 litres

Hydroton media for each bed, 12 inches deep. I am finding it a tad overwhelming at the number of brands

and quantities.  Thank you . Paul

TCLynx said:

Head is figured from the surface of the water that the pump is pumping from.  So if your pump is drawing water from the bottom of a 3' deep tank and the grow bed surface is 2' above the surface of the water then you are only pumping to a head of about 2'.  Always figure a bit extra though and remember that when the water level in the fish tank or sump tank falls, the head increases.

[Daniel McElhattan]

I would love to but I have no idea myself.  Still haven't purchased my pump.

[TCLynx]

You want to look for a pump that will move at least the volume of your fish tank at the height you will be requiring.  (most pumps that are called 1000 lph pumps will only move 1000 lph at 0 head so if your fish tank is 1000 liters you need something bigger than a 1000 lph pump.)

I often like to move more like twice (or more) the volume of my fish per hour.  Add to that, you need to know if you will be pumping continuously or do timed pumping.  If you do timed pumping, you will need to move the volume required in the fraction of the hour the pump will be on.

For continuous pumping of an IBC or aprox 300 gallon fish tank, I'm kinda partial to the Quite One 4000 pump.  It is a 50 watt pump that has worked very well for me in small systems.

[Paul Smith]

TCLynx said:

You want to look for a pump that will move at least the volume of your fish tank at the height you will be requiring.  (most pumps that are called 1000 lph pumps will only move 1000 lph at 0 head so if your fish tank is 1000 liters you need something bigger than a 1000 lph pump.)

Thank you very much for the reply !

All the best, Paul

I often like to move more like twice (or more) the volume of my fish per hour.  Add to that, you need to know if you will be pumping continuously or do timed pumping.  If you do timed pumping, you will need to move the volume required in the fraction of the hour the pump will be on.

For continuous pumping of an IBC or aprox 300 gallon fish tank, I'm kinda partial to the Quite One 4000 pump.  It is a 50 watt pump that has worked very well for me in small systems.