Backyard Aquaponics
A place to discuss aquaponics

Hello all..

I have been reading these pages for some time now and have finally decided to start designing my new system for my soon to be complete house.

I have allocated quite a large patch to build this system in the back corner of my block.. I cant start for a few months yet (probably after winter) as the house is still being built. This area receives full sun most of the day and should create a very nice water feature (part of the wifes stipulations)

At the moment i have a Blue Barrel setup (2 x 100L growbeds and 1 x 100 - 150L tank plus a 60L overhead tank that uses a dunny cistern) that i have successfully used for the last 5 months with about 15 goldfish.

My plan (which is still in my head) is to build a huge fish pond that is part of the asthetics of the back yard with a number of growbeds behind the pond. The pond size will be a quarter circle of about 5M radius and about 1.2M deep. Behind this pond will be the growbeds that all drain into a sump and then to a waterfall cascading down (aeration) back into the main fishpond. These growbeds will be 1.5M all the way around the back of the pond at about 0.6M deep. I would be guessing volumes here but i am anticipating about 10350L of growbeds and the pond will be about 23550L using these above mentioned parameters.

I am trying to get away from using a head tank in my new system (for asthetics again), therefore my plan is to use a pump with a timer to create the flood and drain mechanism with a sump at the base of the growbeds to pump back into the waterfall.. therefore a 2 pump system.

Temp and water level control will be via an Allen Bradley PLC and retic solinoids. i will monitor temp and then send the sump pump supply through either a heater or a refrigeration unit inside my nearby shed then back into the pond via the waterfall.. Level control will be very basic setup with floats that open a solinoid from my rain water tank on a low level only and stop at a high level float. The sump will also have a high level trip for the main pump to eliminate overflow.

Construction will be permenant with bricks and mortar with a concrete base. I would then water proof the internals with a basic pool rubberised paint of some sort. All plumbing will be accessable all the time for maintenance.

As an extra, i will be cascading a flow (overflow to control feed pressure to the growbeds) through my chook pen and bird cage via another waterfall and a small tributary back to the main fishpond. This will assist aeration as well as feed the chooks and birds, but also give the small feeder fish somewhere to hide from the main fish crop. I hear chooks like small fish also..

Anyway.. this is definately a goer... so please critique

hmm very big plan indeed..

My first red flag is the heater / chiller idea. Changing the temperature of 30KL of water is going to be HELL of an expensive proposition..
Here is a cool table to show you what sort of energy you are looking at..
http://www.tempco.com/Engineering/wattage_estimation_tables.htm

500 Gallons will cost 27KWH to raise the temperature by 20degrees.
500 gallons is about 2500L. you have 30KL. so you are talking more than 300KWH to raise temperatures by 20degrees. And of course keeping the temp there will cost too..

Your second issue is with the two pump idea - I understand the need for aesthetics, but you are building a large element of risk into the system as soon as you have a pump in the FT and the GB is not on top of the FT. If (when) a pipe of fitting breaks, you will empty the tank. Of course you could manage this risk effectively by maybe having a float in the FT, and run the pump in series with the float so that it will never empty the FT beyond the float level.

I would suggest digging a second pit next to the FT and have a SLO into the pit. The pump will be in the pit - sort of a mini-sump. If a fitting breaks, the water level will not drop below the SLO level. Preventing your smallfry from getting sucked up in the pump is of course another good reason not to have the pump in the FT.. The water from the pit can then go into the GB and from there empty into the "real" sump, and from there back to the waterfall..

just a thought..

by the way, just noticed that the table I linked to in my previous post specifies the amount of KWH you will need to raise water temps in deg F (not C!)

If your pond is in ground and GBs are above ground level why not just drain from GB straight into pond. The waterfall might not be as big or dramatic, but maybe have the waterfall flatter with water flowing over a rough surface for airation and effect.
That way you only need one pump and just have flood and drain on a timer.
As for controlling water temp, why bother Run Barra in Summer and Trout in winter or Silver Perch all year round, or for a pond Koi and Goldfish are good year round and look great in the water.
Just a couple of thoughts.

Yep, sounds easier and simpler

Pump from the pond straight up to the beds and run the drains straight out the bottom of the grow beds over some rocks and waterfall features back into the pond. Hide the piping with some rocks etc and you wouldn't even know they were there.

You could have a constant flood system or run the pump on a timer, either way would work a treat

Hi Stanga

We are currently building a brick pond with a concrete base in our back yard also for asthetics, then piping water to GB's at the side of the house, just wondering how things are going with your system as it does closely mirror our design.

Steve