Backyard Aquaponics
A place to discuss aquaponics

I want to thank everyone for the input and suggestions.... I think im getting closer to a final design...

here are some new sketchup layouts....

Main GB is 3' x 16' x 1' - 359 gallons - 50/50 ration would leave approx. 179.5 gallons
Additional GB's are 2' x 3 1/2' x 1 x 4 total - 209 gallons - 50/50 - 105 gallons
ST is 2 1/2' x 16' x 1 - 299 gallons
FT is 3' x 3' x 9' - 605 gallons

total water available - ST & FT - 904 gallons
total GB - approx 285 at a 50/50 ratio

makes this about a 1.11 to 1 FT to GB....

From previous layouts, I have extended the FT across the entire side of the GH...
I have decided to use one pump, for ease of timing...

heres how it SHOULD work

the ST is dug in - not much more digging then the barrels...

A fast fill, slow drain system with cascading GB's

using a modified constant flow system, the water flows into the main GB, then then the water will flow down into the additional GB's, then flow further down into the ST..

the Additional GB's are near ground level so I can plant the tall and vine plants so they
wont block the southern sun......

a couple possible different methods to do this....

Using stand pipes I would have to figure out what size drain holes to place in the standpipes for the main GB so im not sure it will be fast enough to fill the additional GB's before they drain....

or

Maybe I could just use 4 overflows on the main GB to feed the Additional gb's, like I do from the FT to the main GB.... just keep the pump running long enough to fill both. by keeping the overflow pipes 1" below the medium, I could keep the surface gravel dry...

anyway its open for discussion

hope to start building by spring.. as soon as I get all the plants out

Cascading is fine, I do it, but I wouldn't recommend it with slow drain the drain from the first into the second will just be too slow.
If you wait until all are filled, then the bottom will be filled for a much longer time

If you use siphons however, and just put a float in your sump, you're guaranteed to fill the top bed before the sump runs out, and then the bottom bed will fill as the top bed drains, then when there's enough water in the sump again, the whole process will repeat.

Going back to slow drain however... I don't like it. I think you will have problems getting your bottom beds flooded. If you pump until they're flooded, your sump will be nigh on dry and the top bed will be very wet.
Similarly, if you don't you can't guarantee the height of the flood for the bottom GB.

Your design however lends itself to be changed to siphon or not cascaded at a later date, so if you want, just give it a try... you'll want to get all the bugs worked out before you get fish though.

I agree that slow drain probably won't work for all the levels of a cascade. You need some method of auto draining from one of the levels. Easiest would probably be a Flout for the top bed that would then quickly feed the lower beds and you could allow them to slow drain. Trickiest part would be to make sure you have a timer that can shut off shortly after the flout sinks so that you don't risk starting to refill the top bed after the flout pops up again. Only reason I recommend the Flout over an autosiphon to feed the lower beds is that you have very limited fall to work with and the flout doesn't much care about flow rate as long as the pipe is big enough to carry the flow. The problem you may have trying to get siphons to work is that you don't have any extra fall to work with which usually makes things tricky.

The main reason I'm not recommending the top bed be slow drain the the bottom beds be siphons is that the slow drain might not be able to over top the siphons and kick them in and thus the beds would remain always flooded so no good. The reason I don't think you would want Flouts in the bottom beds is that they take up space. However, you might think on perhaps an external Flout for the lower beds. It would require a separate container (storage bin would probably work) and connecting the bottom beds together with large pipe so they would flood and drain as one (each bed should still have an overflow installed though). Install the Flout contraption in the external bin and when the water reaches the right height the flout sinks and drains the beds.

Then again, the float switch idea might just be the ticket. You would need a fish/drinking water safe float switch that can handle the wattage or amperage of your pump or you would need to wire up a float switch that would operate a relay that could turn your pump on and off.

hi..

thanks again... for the info..

I looked for a flount, but only found a hand drawn sketch, and didnt make much sense to me...

maybe I didnt explain right which happens often

I would not rely on the standpipes to fill the bottom GB's, I would have 4 overflow pipes positioned 1" below the top of the gravel in the side of the main GB so it wouldnt overflow, the pump would be timed to fill the main GB and keep running thru the overflow pipes into the bottom GB's so when the pump stopped the gb's would then rely on the standpipes to drain them... the only thing I would worry about is if the pump kept pumping..

so I think I would rather have siphons in the bottom GB's, they would be filled independently so no worry about timing there....

I will have 55 gallons left in the ST when all GB's are full.... not counting 605 gallons in the fish tank that would be available if an emergency happened....

I will set up a test system after the holidays to try out different approaches... and see what works best

thanks

Since as you say, you have enough sump volume to flood all grow beds at once, the simple way to deal with this is to feed all grow beds from the overflow of the fish tank.
(don't bother with cascading them)

Simply run plumbing from the fish tank overflow to the main grow bed as well as to the other grow beds. Let all grow bed drains and overflows drain back to sump. This will likely simplify your plumbing and let you do slow drain and use a timer on the pump. Benefits here are, solids get distributed to all grow beds, you already bought that powerful pump so doing timer operation is already a good idea for you, and plumbing is simpler (no need for trying to balance 4 overflows to evenly fill the lower beds etc.) Pump timing will probably also be simpler since you only need run it long enough that all beds are flooded and then it can shut off at the next available increment on the timer.

A good idea to think on when you dig your sump. Make a slight well or lower spot in the bottom where you intend to draw your pump inlet from. It might be good to have the sump bottom slope to the pump inlet and make that area lower. And then if possible, install a float valve below the level of your normal low water level in the sump so that it will only top up when the water in the sump drops below normal and won't top up too much and cause your sump to overflow when the beds drain. This can help you avoid running your pump dry and it only tops up when needed and usually only a little at a time so if your source water has a different pH from your system, it won't be as likely to cause huge pH bounces. I've been quite happy with the plastic top up valves from tractor supply usually used for watering troughs. Only problem is you need about 4 inches of depth in which to install it and half of that should be below the normal low water line.

thanks tcl...

i will look at flooding both sets of GBs at the same time.....

only thing I see is the main GB is 180 gallons (with gravel) and the bottom GB's are a total of only 94 gallons with gravel)... so the lower GB's would be pumped with the same
180 gallons at the same time which means I have to move 86 gallons someplace while the pump is running... not sure how to do that yet....

another idea to look at....

by spring this system will be good to go with all the good suggestions....

thanks all

jT

I'm confused. If the Sump is 299 gallons and the growbeds (all total) require 285 gallons to flood them all at the same time, I don't know where this 86 gallons needs to be moved? So long as all beds are equipped with stand pipe overflows then any extra water going to one bed or another will just overflow back to the sump and no problem.

Perhaps you are wondering how to balance the flow from the fish tank to get the right amount of water to the different grow beds. You might best do this with some ball valves or by making the pipes that feed the smaller grow beds smaller than the one feeding the big grow bed.

I expect balancing the flows to the different beds will probably be about the pickiest part of this set up.

right now I have 3 lower GB's the same size and one smaller so I can get in the door....

ball valves are something to look at....

below is the water flow layout as I see it right now.. but im sure it will change....

"change is good, as long as you do it on paper first"

Yeah... still don't like cascading without siphons in the top bed siphoning into the bottom. Slow drain on the bottom is ok.
Your 'Full' time will be very long with your plan. Many plants don't like wet feet.

The other option for slow drain is, 2 pumps, a fancy timer that has 2 switches (NOT 2 Timers, this is disaster) and pump independently to each.

I must say JT, your sketchup skills are great.

Think about letting the fish tank overflow into a big pipe that can then overflow into the big grow bed and into other pipes that overflow into the little grow beds. This can all probably be done with pvc pipe and fittings that need not be glued together at least not till you get the flow rates right. Use slip Ts (if angled right, you might not even need valves) and slip ball valves if needed. This pipe could run along the side of the big grow bed near the little grow beds and just T off for each bed. Cap or elbow on end for last little bed. Reducing Ts and elbow might be all that is needed to balance flow but more likely you need some valves to keep the first bed in line from getting all the flow.

I would have drawn it for you but I never managed to make good looking pipe or fittings in sketchup.

hey tcl...

actually I drew the water flow in flexi sign, its my progam for making signs.... actually easier then sketchup LOL....

anyway... I was thinking with either standpipes or siphons in the small GB's.. it wouldnt matter if the smaller GB's kept receiving some water from the large GB... but I will set up a test system after the holiday on a small scale and try different things out.....

this is what the inside of my GH looks like right now... will be cleaning it out in the spring and start digging LOL

thanks
jT

maybe we are using the wrong denomination: shouldn't that be called a fast fill, constant drain?
room for a nice new four letter word: FFCD

to my opinion, the FFCD runs less risk of leaving your plants with wet feet than a siphon does
certainly if the pump is controlled by a timer

because: how do you regulate the timer so that it runs just to the moment when the siphon kicks in?
if it is ran too long (till after the siphon kicks out), still some water will be pumped into the growbed to a difficult to estimate level
and the plants will have wet feet
if it is ran too short (till before the siphon kicks in), the plants feet will stay wet at least until the timer activates the pump again
and most probably for long after that because it is very likely that in the next run the pump will run for too long
or again for too short a time
never really dry feet except on coincidence

I have noticed this phenomenon in my system and it has worried me

in a FFCD system, the regulation of the timer is far less critical:
the pump runs, the growbed is filled (to whatever level, even if not to the overflow)
the pump stops
the growbed drains
straight to the bottom

speed of draining can be adjusted easily
so can the period of "dry" feet:
it is the interval on the timer before it actions the pump again.

so , to me, the option of separate pumps, one for each set of growbeds, becomes more and more attractive

and if one timer is not catastrophic, why would two or more timers be?
you either trust timers or you don't

apart from the timers it would surely stay a very simple system

but there are a lot of consequences
... so I'm learning here, thanks all for the assist:

... dig in the fish tank, have the pumps in this tank or in a small tank (=sump) next to it into which the fish tank overflows (still CHIFT PIST ...)

... no, I'm going too fast, I need to think this over

frank

Hey

FFCD sounds good to me..

I was thinking instead of using bell or other siphon, I would use stand pipes, this way if one of the smaller beds got to much water, then it would just drain off thru the top of the stand pipe.... after all beds are filled... then they would drain with adjustable standpipes...

timing the pump to shut off would take a few test runs, but would eventually Im sure it could be dialed in....

by the time I start building in the early spring, I beleive between me and the entire AP community we will figure it out the best possible solution....

thanks
all

Have a look here ... http://www.backyardaquaponics.com/forum ... f=8&t=1468

And a manufacturers link ... http://www.rissyplastics.com/flout/about.html

Here is the part of my thread where I installed the Flout
http://backyardaquaponics.com/forum/viewtopic.php?f=18&t=2640&st=0&sk=t&sd=a&hilit=flout&start=410&sid=ae2dc1dc5b4a44589cd56c28b10b9594