Flow rate discussions

This thread is a continuation of the original discussion by Atom here.
Please continue to post your questions in this thread.

Some information you would need to provide:
1. Tank size
2. Height of the tank (from the pump) - you need to do a measurement
3. Flow rate of the pump/cannister filter in liters/hour given the height (check the chart on your box)

Personally, I recommend a tank turnover of 4, but if one don't mind the additional electricity costs, 6 would be nice.

[Ryan Red]

me start ,

1)tank sizes => main 6x 2.5 x 2.5H , sump 5 x 2 x 18"H.

2) pump to tank => sump start (up 2ft , across 5ft. ) + tank (up2.5ft x across 5.5ft) so wat is mine overall height?

3) 2 x eheim 1264 => 2 x 4500l/h (over kill flow rate?)

Your 1264 has a flow rate for each height. Check the box for 4.5ft

Originally Posted by Ryan Red

me start ,

1)tank sizes => main 6x 2.5 x 2.5H , sump 5 x 2 x 18"H.

2) pump to tank => sump start (up 2ft , across 5ft. ) + tank (up2.5ft x across 5.5ft) so wat is mine overall height?

3) 2 x eheim 1264 => 2 x 4500l/h (over kill flow rate?)

Bro Ryan so coincidence our tank dimensions the same!
Pump running 1 X Rio 32 , stated 8500l/h if I remembered corrrectly, didn't really quite understand the l/h. It got different l/h at different height . Please do advise isn't enough. Thanks in advice.

Does the ht only referred to the up ht , must we also include the across and return? My question might sound silly, paiseh .

Originally Posted by plecperu

Does the ht only referred to the up ht , must we also include the across and return? My question might sound silly, paiseh .

I would say no only the up height. Against gravity! haha

[Ryan Red]

Originally Posted by Spakase

Your 1264 has a flow rate for each height. Check the box for 4.5ft

it stated 3.5m maxH = approx. 10ft lol

[Ryan Red]

Originally Posted by Floppy

I would say no only the up height. Against gravity! haha

mean my overall height from sump to tank = 5ft la.

[Ryan Red]

let me rephase,


1)tank sizes => main 6x 2.5 x 2.5H (955.69L) , sump 5 x 2 x 18"H (382.28L).

2) pump to tank => height only consider up = 5ft

3) 2 x eheim 1264 => 2 x 4500l/h, support max H = 3.5m = approx. 10ft


(assume idealy 4 times turn of tank volume = 955.69 * 4 = 3,820L ) over kill liao
(assume idealy 6 times turn of tank volume = 955.69 * 6 = 5,734.14L )

That's the max del, what you need to have is the flow rate given a height of 4.5 ft. There is more head loss as the distance widens from pump to height of return pipe. Check the chart for the flow rate in liters per hour.