Backyard Aquaponics
A place to discuss aquaponics

Not usually (unless I don't understand slow drain) inflow at one end of the gb, standpipe at the other end.


Overflow is so you can be sloppy with your pump timing, sloppy's great, cos water velocity varies all over the place. Design as much slop in as you can :-)

The pump pumps from the ST into the GB
The GB drains via standpipe into FT
FT overflows (achieving CHIFT PIST) into the ST.

Or if you like:

The pump pumps from the ST into the FT
the FT overflows into the GB
the GB drains via standpipe into the ST

Which ever suits you best... same outcome, just different layout and convenience.
With slow drain probably better to pump into FT for airation reasons, as Slow drain is slow, and doesn't have much velocity to shake up the water.

Auto siphons work in EXACTLY the same way.
the only difference is that siphons are FAST, therefore the need for timing is non-existent.
Siphons dump a lot of water fast, (preferably) into your FT, thereby aerating the water.
Siphons also suck with such a force, that they draw oxygen through the gravel, feeding the bacteria with nice oxygenated water.

Siphons work Perfectly once you get them right. loop siphons can be tricky.
There is NOTHING tricky about bell siphons. Nothing at all.. .they just seem to WORK.
The only thing you need to do is vary your flow rate to suit your siphon.

(Can you tell I'm a fan of siphons)

Either way the basic principal of plumbing is simple. Water shouldn't drain back down through the pump. The pump will cause much resistance, and it may not be good for the pump. also, many pumps have one way valves on them, making htis impossible.

Yeah, just like in OB's drawing.

the barrelponics group prefers buried fish tanks and elevated growbeds to CHIPT PIST.
so there is no sump, sometimes (mostly) there is a top tank with an autosiphon, which regulates the "fast flood", "slow drain"
when I advocated CHIFT PIST on the barrelponics forum, I met with fierce opposition
with a lot of arguments I could relate to, (like temperature fluctuations)
but also with arguments hat were limited to sheer conservatism

in these systems the water always comes back to the fish tank (where it came from)
come to think of it, all systems do eventually
there is nothing wrong with this as long as biofiltration is ensured
normally that is accomplished by top flooding and bottom draining
this way the returning water doesn't flow back through the pump (wherever that is located).

say (like in the barrelponics setup) the pump is in the fish tank and there is no sump (else you would need two pumps)
the pump pumps to the top of the growbeds which drain from their bottom back to the fish tank
no backflow is happening through the pump

say the pump is in the sump:

I have one CHIPT PIST system working with a 1000 l IBC fish tank filled to the 800 l mark and two sets of three (1/3 200 l plastic barrel bottoms) growbeds (a third set of four beds is still waiting to be connected) with only one bottom connection to each growbe, used both for flooding and for draining.
70 x 10 = 700 liters growbeds volume, so the 1:1 ratio is just about respected
the fish tank overflows into a gutter (I call this the the distribution gutter) that overflows into the growbeds (through their bottom) where the water is held until the autosiphon (one bell siphon per set of 3 growbeds, mounted on the exterior) kicks in.
the outlet of the autosiphon is quite a lot larger than the inflow, so the growbeds always drain completely to the sump in which the pump is located, even when they are simultaneously refilled.
this system has been running without mechanical problems for 3 months now.

more details on this system:
to avoid a recirculation of solids I have incorporated an between the fish tank and the distribution gutter
so actually the fish tank overflows into the upflow bead filter which overflows into the distribution gutter

the pump on this system has turned out to be too big in relation to the overflow pipe of the FT, so I can only run it for 10 minutes at a time lest the FT overflows (to where I definitely don't want it's contents to go).
my (standard) timer only allows for 20 programs/24 hrs so, spreading these, I have only a 10/60 pumping ratio for 16/24 hrs and a 10/120 ratio for 8/24 hrs (if my mathematics are right, let's check: 16 + 8 = 24 hrs)
this means the pump only runs 160 + 80 = 240 minutes/24 hrs, which is not enough to my liking.
but I have only one type of pump and I want to keep it that way.
... and this timer sometimes forgets it's programmation. on average once a month.

as soon as my main electric cabinet is installed I plan to replace this timer with a small Siemens Logo! PLC (or, as Kuda rightfully prefers to describe them, a programmable relay) which will allow for much more pumping i.e. 10 min on, 10 min off, 7/7 24/24 (or whatever).
this PLC will allow me to regulate 4 or more of these systems simultaneously but with different, independent timing.
or allow me to do a lot of other things like sequenced flooding of growbeds and water quality monitoring.
it allows for maybe 100+ separate timing operations (I should check the numbers) and have each one of these subjected to a multitude of conditions (like a ph, and/or a level detector and/or a thermostat) on each separate circuit.

I have used them for many years on automatic cleaning systems in the food industry, for very complex circuits, so I know I can rely on them. almost absolutely.
certainly more than on a standard timer.

these are truly amazing little pieces of equipment, and the fear that using them would be a digression from the KISS principle is unfounded if you accept the use of standard timers.

excuse the eulogy (no, I am unfortunately not sponsored ) but I truly believe that the step from a conventional timer with it's very limited possibilities to this equipment is a very small one to take.
I was very reticent at first, but now I am a believer.
I am ready to assist in programming them.

I can feel what is coming, and yes, one day I will gather all these descriptions on a thread dedicated to my system
But I am the one who decides when I will be ready for it.

A question?
I have a BYAP 3 GB system with a 2000L tank been in just over a month and doing really well, congrats to Joel for a fantastic kit
I have my set up right next to a 30,000L swimming pool, come the end of summer I have a dream to de chlorinate the pool and get some trout in there, drop the pump supplied in the deep end of the pool and use the supplied tank as a drain tank
I have access to 10 x IBC's, I understand the tank to grow bed ratio but what is the ratio for fish density to surface area of grow bed media, as IMHO that is the ratio that has the relevance?
I could be wrong? I was once before
If I have to put in 30 x IBC's I will have to pitch a tent in the park next door to live in?
Once I figure out how to get some photo's posted I will do so, I cant even cut and paste one of those smilies in the panel right next door?
Cheers Solarsparky

the ones next door - just click on them no C&P
or view more smilies...

Like this?

yep

I think it would be about 3kg of fish per 100 l of grow bed.

More grow bed is always fine and more water is always fine but you need enough flow/aeration and filtration to support your fish.

Cheers TC Lyncx I'll run with that till we here better, still a few months of hot weather yet before the family let me take over the pool.
Bundaberg Kid by all means go and get a life

there is discussion on this issue
TMHO fish density is related to recirculation rate
and should not be expressed in kg/m³ but in kg/m³/hr

frank

Only partially Frank... ultimately it's more related to filtration capacity.... which in itself can be influenced by... or limited by flow rate...

The figure given and repeated is a "safe" density ... and an easily calculated guide...

Most people wouldn't probably be able to measure there flow rate anyway....

And stocking at the suggested density with the style of media based growbeds has been demonstrated to work ... consistently.... over and over again .... for everyone....

With experience, and or alternative equipment... higher densities are acheivable.... with correspondingly greater costs, time/monitoring involvement and greater risks....

We're talking backyard aquaponic systems.... not high intensity RAS systems... or commercial scale operations....

IMO... floating raft.... and pre-filtered delivery to NFT.... may scale better to commercial reality than growbed systems....

But involve adoption of auxillary equipment... and can be limiting to what vegetable produce can be grown....

IMO... such systems... focus more on fish farming (aquaculture).... with the plants becoming a secondary stream.... a way of dealing with nutrient waste water...

Most people here look to aquaponics as a "balanced" system of fish and vegetable production ... with minimal cost and maintenance...