pipe widths for AP system, flood and drain

[Tina Cresswell]

Hi, I am installing the flood and drain system now, and I wonder if I should be using 1 inch pipe (flexi?) to deliver the pumped water from the sump tank to the grow beds, and then 2 inch pipes for the gravity drain under the grow beds back to the fish tank?

Any advice please?

Tina

[Fishy McFisherson]

Pipe diameter will vary depending on the flow requirements of your system, but the rule of thumb with gravity fed systems I've always heard from my aquarium buddies, and been successful in the application of, is that your drain should allways be at LEAST 150% the size of your feed. If your system needs a 1" feed, a 2" drain should be enough. 

Mild tangent, if you were evenly splitting water flowing from the 1" feed to 2 beds, you could theoretically get away with 1" drains on both feed and drain piping, which would make it easier when it comes to buying fittings.

Anyone else have thoughts/experience on this?

[Ian Cameron]

Fishy is right, it depends on the flow required to adequately circulate your fish tank and your ebb and flow system. My system is not large, being an indoor pilot project. It contains 3 20gal  Rubbermaid containers. 1 being fish tank and 2 being biofilters using Hydroton. The pump has 3/4" pipe, with a manifold to the biofilters and return line to fish tank for excess water. My system fills/drains about every 10min. The drains are 1' black plastic right through to the top of the siphon, and have worked without fail since day one. The one thing I found out is that if I tried to extend the fill time to 15min, my siphons would not work properly, they just trickle water through without creating the necessary vacuum to start the siphon. I figured out that a 1/2 syphon would work better, but my water tests are ok, the spinach and chard are growing like crazy and the gold fish are getting downright fat and happy. I'm happy, the wife is happy (thank goodness). Happy wife -Happy life. Don't know if this answers your question, but there it is.  Cheers

[Tina Cresswell]

Thanks Ian and Fishy, that's really helpful, hope to be up and running in the next few weeks, will let you know how it goes!

Greetings to all x

[TCLynx]

If in doubt, bigger drain plumbing is usually safer.  But as noted, will cost more.  Uniseal fittings can often save money there though.

Exact size of plumbing needed also depends some on type of flood and drain being used and as noted, if you are splitting the flows to feed the beds.

Most of my big grow beds all had 1 1/2" plumbing fittings which is good if you are sending a huge gush of water into them and want to make sure your stand pipes won't be too small.  However I've managed with 1 1/4" drains on some of my newer beds and that was ok.  This has been for timed flood and drain stand pipes.

If doing siphons the drain sizing will need to balance properly with the flows to get the siphons to work.

My combined drains are usually 3" and my large SLO drains on the CHIFT PIST tanks are 3".

[Tina Cresswell]

Thanks TC thats very helpful, will be doing the plumbing in next weekend, let you know how it goes!

Regards 

Tina x

TCLynx said:

If in doubt, bigger drain plumbing is usually safer.  But as noted, will cost more.  Uniseal fittings can often save money there though.

Exact size of plumbing needed also depends some on type of flood and drain being used and as noted, if you are splitting the flows to feed the beds.

Most of my big grow beds all had 1 1/2" plumbing fittings which is good if you are sending a huge gush of water into them and want to make sure your stand pipes won't be too small.  However I've managed with 1 1/4" drains on some of my newer beds and that was ok.  This has been for timed flood and drain stand pipes.

If doing siphons the drain sizing will need to balance properly with the flows to get the siphons to work.

My combined drains are usually 3" and my large SLO drains on the CHIFT PIST tanks are 3".