Backyard Aquaponics
A place to discuss aquaponics

Hi guys,

Long time reader, first time poster – thanks for all the information you have put up over the years!
I’ve been gathering all the parts for my own system, and finally looking at getting it set up. It's going to be a CHIFT PIST system and I’m going to start off with:
• 1 x 1000L fish tanks – fitted with 50mm SLO
• 3 x 300L media growbeds with bell syphons
• 1 x 700 L sump tank
• 1 x 3000L/h pump

Pump in sump > FT with 50mm SLO > into all 3 GB’s > sump.


While I’ve done a lot of research and have a fairly solid grasp of most of the concepts, now that I’m actually putting it together I would really love any feedback and will surely have a few more questions!

The first issue I am looking at right now, is the plumbing from the FT to the grow beds. I’m looking at using a 50mm SLO, but I want to be able to control the flow to each GB using ball valves so that the flood rate is pretty much the same. The 50mm ball valves are pretty expensive, so am trying to figure out a cheaper way.

So my first question is, will reducing the 50mm to 25mm and then splitting the flow to 3 grow beds through 25mm pipes work? Or will it have to big an impact on the flow rate from the SLO?

Or would I need to look at splitting into 3 x 50mm pipes and then reducing from there?
If option 1 won’t work, I might as well just buy the 50mm ball valves, but really trying to do everything as cheaply as possible!

Cheers
Sean

Hi Sean,
I know this post is a bit old, but I saw it was unanswered, so here I am.

I don't know too much about flow rates and plumbing, but it seems like your idea of reducing the plumbing might slow the flow a bit. I have seen other posts here that go into the rabbit hole of velocity in plumbing.

I'd be weary of the reduction itself and what it is like internally. I've noticed that places where the pipework has slightly raised bits in my SLO overflow tend to gather waste every now and then. Nothing a good reaming doesn't fix. And, this might be a non issue if you run a rff or other pre filter before the grow beds.

I'm thinking that if your plumbing was all uniform, without reductions, that the last bed might receive the least flow. I'm wondering what might happen if the first outlet pipe was smaller, the next one a size up, and the last one the biggest. I don't know if I'm right, but I would guess that if there was no reduction, that the majority of the flow would come out of the first outlet...???

If you're handy with a saw, maybe the pipe size could be the same, but you could cut end caps so that they have various size openings on the bottom to change the outflow?

Sometimes spending the extra cash for what you want is worth it, especially if you foresee using the system for a long time. Maybe you can find some valves second hand on Gumtree or equivalent?

Did you every get around to the build? How did it go?