Backyard Aquaponics
A place to discuss aquaponics

Greetings from Mornington, Victoria,

Perhaps someone can clarify:- The ABC of Aquaponics suggest that constant running
and keeping the growbeds flooded is the way to go. This would seem to prevent emptying the growbeds
which allows air/oxygen to enter the lower reaches of growbeds. Presumably this will have to happen occasionally?

As I'm trying to design a system I'd like to have it work properly. Any help would be appreciated.

Cheers,
Pramsec

The debate on this will go on and on

Trials show that the 3 basic systems perform very similar AS long as they are set up correctly

Constant Flood / Flood and drain via siphon / Timed flood and drain

Variables on these systems are endless

No matter which type of system is chosen success depends on owners input of time and learned knowledge

With constant flood its important to have multiple water delivery points to the growbeds to avoid "dead areas" . Design must achieve sufficient aeration , good simple systems with less components so cheaper to set up and take up less room , pump has to handle fish waste "solids" in a pump up run back layout .

Siphon systems (my choice) certainly have good aeration and good turnover of water and nutrient through the growbeds . In the basic setup system pumps fairly clean water (no fish solids) fish waste goes to growbeds via gravity . Split level systems that pump to growbeds and fish tank will be pumping some fish solids .

Timed flood and drain can be set up to be more power efficient , better suited to low fish stocking rates .

So with everything it depends , do you want to grow fish to eat or are you happy to just have perhaps some tough goldfish to drive your system and have it plant based .

If you have space you can start small and build on later

If you want to start adding Deep Water Culture Growbeds the design will change , you will need pre filters .

Some idea of your plan for a finished system will help and we love photos.

Have fun and ask questions

Please please dont be over confident with your fish choice... gold fish are cheap and in your learning if anything drastic goes wrong you have not killed perch or brim or barramundi etc etc

Thanks XC & Tonzz,
I shall put together a sketch of what I want to start with and a picture of where it will go in my backyard.
As I have PV panels I would like to operate pumps only during daylight to minimise electricity use at night, at least until
I can afford a storage battery.
I can also present some ideas I might have on details for comment. Your longer experience, I'm hoping, will help me
achieve an economical system. Tonzz, I take your point on using goldfish until I get proficient. Poor Goldfish!

Rather than switching the pump off at night it may be a better idea to look for a low wattage Eco pump. I have one pump that is capable of pumping up to 3600 litres per hour and it only uses 10w of power ( I calculated it to 12euros per year) that's less than 20 AU dollars.

If you select a good quality low wattage pump (35-60 w) and use the timed F&D method you can incorporate a timer with 15 minute intervals which will allow you to have 15 min on / 45 - 75 min off (depending on the season) saving more than 75 % of the pumps rated power usage. Generally the air supply (10 - 15 w) runs the whole time but there are some air pumps that have programmed settings for intermittent use. I don't use it because the on/off switching could cause a longevity issue.
I use solar as well but only stretch out the cycle times at night in winter.