Backyard Aquaponics
A place to discuss aquaponics

Hi guys finally getting around to plumbing our new system this weekend. Most likely going to use PVC unless told otherwise. My main question is whether it use 20mm or 25mm?
Only need to plumb from the pump to grow bed which will have 2 valves. One to adjust flow for a spray bar I will T off the pipe from the pump and another closer to the GB to adjust fill flow.
Any help greatly appreciated

Cheers

What type of pump do you have? Many of them will take a 40mm threaded coupler without any modification allowing you then attach 40mm pipe to it. The larger the pipe the less friction.

Yep plumb from the pump with the maximum outlet size... then reduce down to the grow beds...

The pump is a pond master 3500 lph. 19 mm outlet. We only have a small system as its our first and we only rent. Have uploaded some pics of the build so far.

I'd try and get a 19mm to 25mm adapter... for the pump outlet.... and plumb everything in 25mm then...

Cool thanks rupert. Will pay the irrigation place a visit on Friday. Really need to get this thing finished. I'm sure you guys will be hearing more from me when we finally start the pump.

As arbe said, the larger the diameter, the less friction, less pressure loss from the pump, leading to a higher water flow. In marginal situations the larger pipe could make the difference between just enough and too little flow.

Personally, I ran a 40mm backbone with 25mm outlets to each GB.

You need to work out the head (height from the water level above the pump to the GB), and see how much flow you will get according to the pump curve (probably on the side of the box the pump came in). If you are getting enough flow to turn over your FT every hour and add a sprayer bar, then there is no problem with 25mm. If you need to minimise pressure loss (and maximise flow rate, go for 40mm. Don't worry about the pump outlet, you can always get an adaptor to increase the pipe.

On the other hand, the 40mm valves are a bit harder to turn than the 25mm valves. That's why I stepped down from 40 to 25 before I put my valves in next to the GB. Also my pipe cutters worked on 25 but not 40mm.