Backyard Aquaponics
A place to discuss aquaponics

Hi

I have a question regarding ratios for FT and GB. I have read that the ratio is 1:2.
That being the case does the sump have any consideration on the ratio. Also is the ration considering total literage of the growbed or % of after bed is filled.

Mark

There are so many factors involved, and there's no simple answer. The way I see it, the real answer is probably going to be a formula akin to the following one. Recent research that has provided the mathematical formula for a perfect handshake, which just happens to be :

PH = √ (e2 + ve2)(d2) + (cg + dr)2 + π{(4<s>2)(4<p>2)}2 + (vi + t + te)2 + {(4<c>2 )(4<du>2)}2

(e) is eye contact (1=none; 5=direct) 5; (ve) is verbal greeting (1=totally inappropriate; 5=totally appropriate) 5; (d) is Duchenne smile - smiling in eyes and mouth, plus symmetry on both sides of face, and slower offset (1=totally non-Duchenne smile (false smile); 5=totally Duchenne) 5; (cg) completeness of grip (1=very incomplete; 5=full) 5; (dr) is dryness of hand (1=damp; 5=dry) 4; (s) is strength (1= weak; 5=strong) 3; (p) is position of hand (1=back towards own body; 5=other person's bodily zone) 3; (vi) is vigour (1=too low/too high; 5=mid) 3; (t) is temperature of hands (1=too cold/too hot; 5=mid) 3; (te) is texture of hands (5=mid; 1=too rough/too smooth) 3; (c) is control (1=low; 5=high) 3; (du) is duration (1= brief; 5=long) 3.

Soooo many variables...


Some other things that need to be slotted into the equation of growbeds/fish tank ratios are, fish species, stocking rates, feed rates, pumping rates, pumping cycles, style of system, media used, climate, water quality, layout of components, etc, etc....

Unfortunately there's just no simple answer.. However, there's still hope, because just like with a handshake, most people can usually "just know" a good handshake through experience without having to memorize the above formula. Many of the experienced people on the forum can "just know" a good design, or potential problems with a design...

I know crazy analogy, but it kind of works...

So would the system be CHIFT PIST? then the sump doesn't really come into the ratio of 1:2, but it has to be very large. And generally the growbed side of things is the volume of media.

Hi EB

Thanks for the bewt formula..no that just makes 2 much sense

Yes it will be a CHIFT PIST (CHOP) system. I am currently re evaluating FT size. If sump is not a factor bar providing sufficient water for circulation needed. The FT will probably be around 2kl now with a 3kl sump.

I will continue in my own thread then.

Actually yeah, I did find your thread just after I posted here, didn't put the two and two together that that was your thread before hand..

And I really just wanted an excuse to post the hand shaking formula...

To give you some food for thought Shaker:

Lets say I had a 6,000 litre sump, 10,000 litres of grow beds and a 1000 litre fish tank and ran the whole thing CHIFT PIST.

The sump would be big enough to hold all the water need to flood the 10,000 litres of grow beds. I could pump that 10,000 litres through the 1000 litre fish tank every couple of hours it would overflow into the grow beds and then drain back to the sump.

Would it work? Probably, but would I have enough fish in that small tank to create enough poop to support all those grow beds

I really is about balance. With basic CHIFT PIST you have to have a big enough sump to hold enough water to flood your grow beds, that is critical, the more beds you have the bigger the sump you need,

Or

you use a some sort of sequencing so you don't flood all the grow beds at once and the sump size can be smaller.

When I built my system I looked firstly at how many fish I wanted to keep. For the fish tank I just wanted something that would not be too crowded I then worked out how much filtration that many fish would need (grow bed volume). From that I worked out what size the sump would need to be.

Hope that helps

Thanks FF

I must say i am changing my idea daily/hourly so appreciate all advise that comes my way.

Mark

Oops, that should have read:

"I could pump that 6000 litres of water throught my 1000 litre fish tank etc"

I am sure you get the idea.

I actually like the idea of lots of grow beds. You can only eat so many fish and the value I reckon is in the amount of veges you can grow. It really doesn't take a lot of fish to grow a motsa of greenery

For a basic CHIFT PIST (no sequencing valves)
a fairly good set up is.......

Twice as much grow bed as fish tank and sump tank equal to fish tank.
This gives the 2:1 Grow bed to Fish tank ratio while also providing the extra water needed for flooding and draining the beds.

And of course there are many variables involved and people manage systems with a wider range of ratios but this one seems fairly good for a wide variety of situations while also being fairly stable, able to handle a fairly heavy fish load and providing enough plant space to use nutrients but not so much that a reasonable fish load can't keep up with the plant needs.

when ya'll are talking about a 2:1 ratio (GB/FT) are you talking about over all volume (L x W x H) or are you just speaking of the surface area of the tanks/growbeds ?

Volume... not area...

thanks

Myself I don't use a sump. I pump directly out of the fish tanks into the grow beds. For draining the grow bed I use the same design as a bell siphon but no bell. The stand pipe has a hole in it at the bottom of the pipe just above the bottom of the grow bed. To do this one must have a strong enough pump and long enough pump time to overcome the little drain hole and accumulate water in the grow bed. When the bed fills up with water it overflows through the top of the stand pipe.
jim

Standard overflow standpipe... ala a timed system configuration... but without the timer?

Which would then make it a standard "constant flood" system.... although the small drain hole at the bottom of the standpipe isn't universal in constant flood systems...

You do have such a wonderful way with words

So the timed flood and drain system standpipe is all the same but small drain hole at the bottom. (Near or where exact?)

I am just saying I am novice: The small drain holes should be sized so that the draining would be slower than flooding.
Am I right?

After, lets say 15 minutes, when the pump stops the draining hole still continues draining. By the way, During pumping and flooding interval is the water still draining? (Slower than flooding?).

I am little confused.