Backyard Aquaponics
A place to discuss aquaponics

To All,

First of all I know it is a dumb question, but can someone explain to me the plumbings working sof a sump and tank system.

I'm now looking at changing my design to include a sump.

Do I still only need one pump in the sump or will I require one in the tank as well.

With bell siphons, Can I fill the bed once and drain every hour or will that not be enough.

Looking at having 1 sump, 1 tank, 4 grow beds.

Any advice would be good.

Hi Bunja,

no it is not a dumb question. One issue with AP is the myriad of setups that all function and in cases are variously better than each other under different circumstances. Also the forum is a bit of gold mine with lots of buried treasure mixed in with lots of overburden...

(a) The basic design/s that use a sump are CHIFT-PIST and CHOP/CHOP2 systems. A google search on these will bring up lots of images from all over the web. You can also search within this forum for lots (and lots and lots) of information.
eg. I googled 'chift pist' and 'chop2' and got results and a lot of images.

This forum tends to favour CHIFT-PIST. There are various posts that cover the whys and wherefors...
and it is not my desire to start another new argument for or against here - search and ye shall find the full spectrum of opinion.

there is a glossary at http://www.backyardaquaponics.com/information/glossary/ which has the appropriate title subject text of "What an earth is a SLO or a CHIFT PIST system...."
The forum also has some dedicated threads eg. viewforum.php?f=14

CHIFT PIST - basically Constant Height (water level) in Fish Tank Pump in Sump Tank <<< what you probably want.
CHOP - Constant Height One Pump (with a few variants eg. CHOP2)

so the short answer is you only need one pump *BUT* it must be matched to your Fishtank and sump tank size.

(b) how does the piping work...

as above see the images that get thrown up with Google (and also on this forum in the various systems).

basically you have a SUMP, FISH TANK and GROW BEDS.

water is pumped from the sump to the fish tank.
the fish tank water level 'over tops' into a large diameter pipe that is then fed to the grow beds.
the grow beds drain back to the sump.
there is only one pump and it is in the sump. If the pump fails or sump runs dry then the fish tank (and often grow beds) remain full - the inherent appeal of the system

you can run the system with either continuous flow (pump running 24/7) or with a timer.
you can run the system as a continuous flood, as a timer flood and drain, or as a siphon flood and drain.

one trick of the typical CHIFT-PIST system is to promote the removal of waste from the bottom of the tank using a SLO (Solids Lift Overflow). In this case the overflow pipe goes all the way to the bottom and hydraulic/hydrodynamic head is used to force water into the bottom of the pipe and out of the top (the overflow point controls the fish tank water level).

Search SLO on the forum....
some recent diagrams can be found towards the end of Sydney Chicks thread viewtopic.php?t=26026 (SLO discussion pages 28-32, sketch on 32) where various members have provided feedback. A search of SLO on the forum provides lots of feedback and there is a very good thread here viewtopic.php?f=12&t=25684&hilit=SLO but an advanced search of SLO (see below fig) returns a lot of good things (see bottom fig).

hope this helps to start you off... and gives you at least one reply to read

as you have more specific questions and provide volumes/sizes etc people can assist with more specific answers



Where to find and how to use the advanced search for SLO information

some good topics returned below...

>> With bell siphons, Can I fill the bed once and drain every hour or will that not be enough.

usually the recommended for siphons is 2-3, the issue is more about managing flow rates to get the siphons to fire and stop.

many timer flood and drains only have 1 F&D cycle per hour and function just fine.

you would not want more than 3 (1 every 20 mins) because you need the water to be in the grow bed media for the bacterial processes to occur.

looks like the Figures got junked in the recent forum issues...

you can find the SLO example and results mentioned above here -> viewtopic.php?f=4&t=27201&p=535958#p535958


[edit] most important thing is to keep your pipes and fittings as simple as possible - KISS
some systems around are way too complicated and pipes are major source of potential system failure.

All the advice above is good.
I don’t really want to overcomplicate your planning but some recent issues I have had with my sump may give you some hints, in the event, of future expansion.
I have two pumps in my sump.
The main pump is on a timer 15/45 and supplies the two fish tanks and all the media beds.
The second pump supplies various grow tubes. Originally intended to run 24/7 but for various reason now on a timer 15/45.
The timers are not synchronized.
This results in fluctuating water levels in the sump tank. Roughly about 40 cm. Not much. The grow tube pump however is near its limit at a three meter head. About every third day high water. Main pump inactive full drain down, results in secondary pump overflowing tubes.
It’s the height of the water in the tank that effects the rate of flow in the second pump.
A bigger sump would cure this problem. Less fluctuations.
So go for the biggest sump you can.

Ditto to all above...

Going with just one fish tank below a grow bed works OK... it's the classic single IBC cut in two unequal parts version. But, if you want to use bell syphons, you'll have a significant tidal variation in your fish tank - particularly given that you sensibly want to have lots of grow bed volume. This can be avoided by going with constant flood - where the water level in your growbed is constantly a few cm below the top of the media (about 5 cm).

CHIFT PIST works well for me and seems to be the most popular approach on here. Your diagram at viewtopic.php?f=18&t=27188#p535769 would be a CHIFT PIST system if the water level in your fish tank was far enough above the top of you growbeds so that you could use gravity to get the water to them. And you get to keep those yabbies you're keen on!

You can use your original idea of flood and drain on a timed pump... but, if you want to do that to save power, you might find that running constant flood with a lower powered pump works just as well... there are many effective ways to do aquaponics. Don't worry too much about the bell syphon versus constant flood versus flood and drain thing. If you design the standpipes in your growbed so that they're removable, you can make a bell syphon for each of them and then easily convert it to one of the other two setups whenever you like. Some forum members have strong feelings one way or the other but all three approaches seem to work.

Harking back to discussion on your other thread, a SLO is the way most people get their water out of the FT in the CHIFT PIST setup... there are plenty of discussions and diagrams of SLOs on here... a key thing is to make sure you use a T at the top of your SLO to avoid syphoning water out of your FT.

Using two pumps in parallel as Titus does it is OK... but having a pump in each of two tanks connected in series is bound to cause problems as they'll never be exactly matched for volume.

the above advice to use large diameter pipes wherever gravity is moving your water is key... I have about 1500 L water in my system turning over every 40 mins or so... I used a single 32 mm pipe to get water from my FT to my GBs to start with and found it was too small. I now have two 32 mm pipes coming out of my fish tank but, if doing it again, would use a single 40 mm pipe.

suggest another diagram with some volumes and also your best guess at pipe sizes... maybe even a guess at pump size... you'll likely get some good feedback.