Backyard Aquaponics
A place to discuss aquaponics

I am planning to build my first aquaponics system. I have nearly completed my polytunnel to house it.

Will this system work?

Any changes needed?

Is the sump big enough Im thinking it needs to be bigger and can I grow duckweed in it or is that a bad idea?

What size of pump would I need?

Yep!... it'll work, it's basically a CHOP, or CHIFT-PIST system.

When flooded, your GB will take about 1/3 of it's total capacity in water. So a 1000Ltr Gb will take somewhere around 300-350 litres of water... so yes!... your ST will need to be bigger IMO. I would say at least 500L as a minimum.

You should be turning your FT capacity over every hour, so you need a pump that will flow at least 1000L per hour at the inlet at top of your FT, after allowing for head loss and friction loss in the pipes, fittings etc. I would suggest you need at least a 2000Lph pump, if it's to big, excess pressure can be by-passed and help circulate/aerate your water.

Cheers.

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Mr Damage - a.k.a: Yabbies

Looks like you have the system design pretty much spot on. I would suggest a 3000lph pump or larger, bigger is always better and put a tee in the pump line and direct some water back into the sump to create a swirl motion to keep solids off the bottom. I would also agree a bigger sump.

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http://www.backyardaquaponics.com/forum/viewtopic.php?f=18&t=6817
http://www.backyardaquaponics.com/forum/viewtopic.php?f=18&t=6856

Change the siphon for a stand pipe, use constant flow and 1000L/hr pump and it will work fine. If you want to do flood and drain, 500L sump would be the minimum, 1000L would be better. For flood&drain, 4000L/hr pump.

Looks good, welcome to the forums.
Mark

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Test system (deprecated): viewtopic.php?f=18&t=6894

+1

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Bringing Food Production Home

Snazzy, can't wait to see some pictures.

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Many thanks Wal and Tribe

My AP system http://www.backyardaquaponics.com/forum/viewtopic.php?f=18&t=8299

Home and hosed

really, that much less for constant flood???

and do you mean a 1000L/hr pump or 1000L/hr of flow to the GB?

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My system

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My skills include being able to move slowly forward in time, and if I really concentrate, I can sometimes tell what I'm thinking.

I think you need to add a siphon breaker in your pump line in case of a pump/power failure. In the event of either your FT water would siphon back to the ST with disastrous results. I have used a foot valve for this purpose in the past. Just put a Tee piece in the pipe at the highest point and place the foot valve in the tee so pump pressure holds it closed but if there is any suction the valve opens and lets air in to break the siphon.

Cheers
Dennis

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looks good, but i'd be more comfortable with a little bit bigger sump

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my basement system;
viewtopic.php?f=18&t=8354

Yep... either that, or you could have the water supply outlet from the ST entering at the top of the FT, rather than taking it all the way to the bottom.

The water from the ST breaking the surface of the water as it splashes into the FT would help with aeration.

Cheers.

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Mr Damage - a.k.a: Yabbies

If you do the stand pipe for a constant flood (+1 from me on that idea) be sure to drill a 6mm or so hole at the base of the stand pipe so that you can also switch to a flood and drain if you feel like it. I made that mistake wish i hadn't.

Also, with such a large grow bed you probably need large plumbing, I'm not sure what would be best but keep that in mind (and a 6mm hole might not be enough).

Oh, and I agree with Mr Damage. You want to overflow the water from the fish tank from the bottom (be sure to use a T at the top so you can't get a syphon), but let the water from the sump splash in at the top. This adds aeration, and pulls the solids into the grow bed where they can do some good.

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My Aquaponic Mini System

Yes, that much less. As pointed out earlier, you want to turn over the tank once per hour. With F&D, you will do that in 15 minutes...thus the 4000L/hr pump. With constant flood, you will turn it over during the entire 1 hour....thus 1000L/hr.

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Test system (deprecated): viewtopic.php?f=18&t=6894

As Deja said, if you are running constant flood, turning over the volume of your FT once an hour would require a 1000 L/hr pump. That is, 1000 L/hr at the required head. When you go to buy your pump, make sure you know how high you need to pump the water, then check the chart on the box to be sure it can more 1000 L/hr at that height. You may need to buy a 2000 L/hr pump or better as the pumps are usually rated at 0' head.

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Really? I would have said that if your getting solids in your sump then your filter (ie your gb) is not working properly.

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Yep...

and as I said early on in the thread, I reckon the water from the ST should enter at the top of the FT, possibly providing some aeration as it does, but...

the gravity feed outlet from the top of FT into the GB should be a solids lifting set-up, picking up the water (and solids) from the bottom of the FT and dumping into the GB.

Cheers.

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Mr Damage - a.k.a: Yabbies