Backyard Aquaponics
A place to discuss aquaponics

Hi to all the NSW AP' ers

My first post ever to anything & the screed below may be too long & boring..........

I am in Martins Creek, north of Maitland. Hot as hell in summer & chilly in winter..hmmm...needs thought to keep the system stable & fish growing to achieve target outputs of 5 fish at 825gm per month & all the veges my wife & I (& 6 grandkids) can eat.

I have not AP experience but continue reading & avidly........here goes ........

I am in the process of designing my system based on info from this site, Joels 113 pages etc & would really appreciate input & advice on the practicallity of the following.

950 litre fish tank, for Silver Perch at fish density about 0.03 Kg per litre, housed in a well insulated corro greenhouse, together with 2.7sq m grow bed and Sump of about 1000 litres for water draining from the inside bed and further grow beds totaling 2.7 sq m which are just outside the Greenhouse. Grow beds are to be 300mm deep. Grow bed volume is therefore about 1620 litres, giving a grow bed volume to tank ratio of 1620/950 = 1.7. I am hoping this will be sufficient for the fish densities proposed. 1 pump proposed to lift water from the Sump to the tanks. Constant water level held in the Tank. Overflow tank water drawn from the base of the Tank as water is pumped in from the Sump. Propose 37 minute flood & drain cycle to grow beds. Probably looking at max of 0.5 turnovers per hour of Tank water through the grow beds. Water to drain from grow beds by gravity to the sump. Will possibly set up to flood & drain inside grow beds only at night (cold in winter outside) and both inside & outside grow beds during the day. (This will probably require 2 pumps on independent timers). Hopefully the greenhouse will help hold an air & hence water temperature up to levels where growth of fish is reasonable. Grow bed drain rate to be controlled by either gate valves or pipe end caps with different sized hole drilled in them. If power fails, grow beds will continue draining and all the water fits in the sump.

I think the fish will grow to 825 size in a time frame between 8 & 18 months depending on conditions. I am punting for 12 months (2.5g per day per fish)......help The Tank would hold 3 or 4 cohorts of 20 or so fish with a new cohort added every 4 months. This gives the approx fish density of 0.03. I think FCR could be about 2.....help. I think output of fish will vary greatly depending on system conditions & temperatures & would appreciate guidance on this. I am hoping to hold temps in the range 14 to 25 degrees C.

Not sure about the final Tank water turnovers required to get water quality at the fish densities proposed.....help. Not clear yet on the type of pump/s & the suggested capacities & pumpiing rates, but not overjoyed about buying cheapy pumps......help

I hope I havnt bored you wittless.....I look forward to your input.
I will start a thread as I proceed.


Until next time..........

Warners bay Rupert. Would be great to see a system up and running in the flesh. Cheers mate have a good weekend!!!!!!

Lake macquarie area

Yet to find anyone around my area..... maybe GC the closest

Humm... systems at Lampton (2), New Lampton, Jesmond, Toronto and Cooranbong

I doubt you can acheive 825 gms in 12 months... even with Jades... unless you're prepared to heat the water above 18-20....

Even with heating... Silvers wont reach that size in 12 months... and at 14 degrees, probably wont eat more than every day or two during winter... and if they eat, will only consume about a third of what the would during summer...

Thanks Rupert for the advice on "Growth of Silvers". I have found it difficult to source info on growth rates - still searching the web. Do you recommend any sources I can use. What growths do you think I should target if I hold air temps 17-22 deg C.

"Tank water turnovers" - does anyone have experience to give me guidance on what I should need if my fish density is about 0.03 & my grow bed volume to tank volume is 1.7:1. Will it vary winter to summer with the changes in feeding rates as temp changes.

Quentin

Hi redrocket

I am in Edgeworth if you want to have a look at our system..

I am getting some trout tomorrow afternoon, so that should really get things going.

Cheers again Rupert how would I get in contact with these people.

Ha rosy would be keen to see ur AP system. How's going for u. I still can't decide on what species of fish to use. Nilly ready to start planting, than fish wen I decide. How would I tee up a time to have a look rosy. Very keen to see other set ups. Cheers rosy hope to hear from u.

Keep trying bushy. I got lucky, few close to me

Hi Rupert

I am making headway on finding out info on Silver Perch growth rates & feed rates for different temps - thanks to some of your past posts, various DPI & Dept of Fisheries, Rolland, Dungog, etc articles........Im learning.......any help appreciated but I dont expect to be spoon fed

Regards
Quentin

Hi there Quentin... so you are saying you have 28.5 fish hehehe just the ratio given .... I have 150x 300mm+ Jades in one tank and 700x 150mm jades in aother tank.... Their eating varies dramatically.... During Spring Summer and Autumn they chomp on food like its going out of fashion They eat approximatly 2.5 full containers of food (the container I am talkingabout is the 170G tropical fish flakes screw on lid container) every daythey sometimes havehalf in the morn8am half at 4pm .... during the winter period they start dropping off their food oncewater gets to 22 degress and pretty well stops once it gets to 18degrees... they will eat 1/3 of that samecontainer every 3-4 days.... these figures are from each tank so everyday in summeretc I go through 4-5full of food and they still look for more... I also feed them zuchinnis cut in half and float middle down...Lettuces, celery leaves, zuchinni leaves, frozen peas, caterpillars, worms, BSF larvae, snails, feederfish....But we are talking about feeding 850 - 900 jades

As for growth rates Jamyie I think has agreat thread on Jade growth rates taken from everyone that wanted to put the info in and she even graphed it somewhere.....

Yep, but you're talking Jades... and Jaymie is up around Townsville... where water temps are significantly higher during winter... as are yours DD....

Quentin is in an area where winter water temps could drop as low as 10 degrees.... and I'm not sure that Jades will survive...

That being said, I have seen some large Jade Perch that were grown out... in outside tanks... in the Wyong area...

As I said, a lot of my clients, and myself... will be trying Jade Perch this summer (if we can get them early enough)... and into next winter...

Silver Perch will begin to slow down once the water drops to about 18... but will still eat half rations (related to summer).... as long as the temp stays above 15/16.... once the water drops to about 12... they basically wont eat more than about once a week...

Although they will nibble on lettuce and silverbeet leaves, and algae on the tank walls... and will almost always take live worms,,,

Hi all you NSW AP'ers.....

Does anyone have experience & advice for heating a greenhouse to keep the temp for Fish Tank & growbeds inside the greenhouse to 18 deg C when outside temps drop to 10 deg C ??? (My greenhouse is insulated corrugated iron with fibro lining with louvres all along the front facing north.)

What is the most efficient approach
1. Heating the water....what ways are best?
2. Keeping air temp in the greenhouse up to 18 deg...what ways are best?
3. Other some that are relatively easy include - insulating the outside of the tanks, lids on the tanks, blinds to pull down over the windows at night... any additional ideas??

Investigations to date have led me towards holding air temp to the desired level as the preferred. I would be interested in opinions & experience of others

Till next time

Bye

Quentin