How many chickens per pipe feeder?

[Lahti35]

I'm going to go with the vertical one opening pvc pipe feeders in my coop as space is tight. I'll have 20 chickens to start once they're out of the brooder... how many pipe feeders should I make?

 

[flocking-crazy]

Hi I have 6 birds and 2 feeders, the seller said that 1 feeder can feed up to 8 birds but I think that's just because of quantity of feed it holds, there can be fights at first feed and last feed as only 1 bird can eat at one time, I think 4-5 for 20 chooks should be ok.