How to calculate head pressure through Python hose?

[Trigger88]

All I can find about head pressure is 1 foot per vertical foot, 1 foot head pressure for every 10 horizontal feet PVC and 1 foot head for every 90 degree elbow. But what about a 50 foot Python hose that is laid out on the floor with lots of twists and turns? You can never get it straight. I get that 50 feet translates to 5 feet of head, but is there an additional loss for all the twists and turns when you lay it across the floor? Is there a rule of thumb? I can’t find anything in web searches.

 

[wvned]

I have never heard of one. The length and shape will reduce flow.
If you need to know you can measure it by running water through the hose into a 5 gallon bucket that has markings on it while you time it.

 

[griss]

I have never heard of one. The length and shape will reduce flow.
If you need to know you can measure it by running water through the hose into a 5 gallon bucket that has markings on it while you time it.

Good, practical answer. I’m sure there’s some mathematical calculation but, I’m not good with math so

 

[wvned]

Good, practical answer. I’m sure there’s some mathematical calculation but, I’m not good with math so

I have seen them for PVC rigid but flexible is completely different. To start with it isn't smooth inside.
So laminar flow. How much calculus do you want to do on your fish tanks.

 

[Grin Reefer]

Just out of pure curiosity, why are you trying to figure the head pressure? Are you using the Python in a non traditional way?

 

[wvned]

In my case I wanted to know how much water was being drained by time for water changes.