Backyard Aquaponics
A place to discuss aquaponics

Hey food growers,

I would love to join your ranks, but am concerned re water restrictions, present & future, In Melbourne.

Can anyone tell me the minimum amount of water to build a 1 fish tank & 1 vegie bed system? What are the ongoing top-up requirements?

I haven't bought the book yet, as I am not sure I have the space & about the water supply.

If anyone can give me some rough estimates, I would be very happy.

Welcome Vegiegirl,
What are your goals? If you want to do a little science-project style AP setup, you might be able to work with a 50-100 liter fish tank. If you want to be able to eat some of the fish, it will go larger. My "big" setup holds about 500 liters (125gal) of water in total. I intend to get a fish meal for the family about every other week through the year. Someone else here (can't remember who) has a similar sized system and intends to get a fish meal each week. (I think he has better growbed space than I do.) Top-up requirements will depend on whether your system is subjected to the great outdoors, and whether the tank is covered among other things. Control of evaporation loss is key. A few of us us the nutrient-laden water to feed external plants, but many of us recirculate all water, just topping up for evaporation.

I fill my tank with rainwater, and we've had no problems in the drought - our total storage is 11kL - half of that in rainwater tanks, the other half in fish tank storage. The lowest we got was about 50%. capacity.

I run my fish tank and oxidation process in a greenhouse and feed the plants in an 'open loop'/satelite system.

As I was looking around here, I am sure I ran across someone who had a 55 gallon aquarium with a 2' X 4' growbed on top. That would take up very little space and very little water. It might be a good place to start and you can always use these supplies in a bigger system if you decide to expand.

VG, here is my 20Cents on the water issue.

I have a 1000L fish tank that i filled when water restrictions were in place, and have also emptied and refilled due to a disease in stage 3 restriction.

I justify this by knowing that while i was away in perth for a week and we had 5 30+ days and 2 38+ days, my;

4 tommy plants
1 chilli bush
2 strawberry plants
2 watercress bushes
yarrow
2 basil bushes
sage

All grew well and consumed around 200 litres for one of the hottest weeks we've had.

In comparison, when i emptied my tank last i pumped it onto the lemon tree at about half mains pressure and flow, i pumped 700 lts in less than 30 minutes.

SO, what i'm saying, is that if i watered my lemon tree within the law (cant remember what days and times, but its twice a week) i have used the amount of water (1400L) that could have sustained all my listed plants for SEVEN WEEKS.

See what i'm saying?

Don't feel bad about having to use water on your AP system.

Another way that i relate it is that you'll be using a FRACTION of the water for a given amount of veggies than what the primary producer would if you bought it at safeway.

Pitty help red tape pusher that has a go at me for my use of water

Oh, welcome!

What suburb u in?

it's a hard question as it depends on a lot of factors and variables. like is your tank going to be covered, if so heaps less loist thru evaporation.

i have no guilt in topping my system up with tap water although i 99%use rainwater, the system uses less water to suipport 200 barramundi and all my vegies than my 2 dirt tommies and one capsicum. and take a look at the plants in my thread monya's system to see how good they look.

Thanks guys! That's it, I'm off to buy the book & get started!
Need to read about grow bed space/design etc.
I want to eat the fishies, if not every week then every other week will have to do.
I want to grow vegies too, as I need more space for those that doesn't fit in my present garden, or aren't doing well on stage 3 (ie strawberries).
I probably will now consider some kind of removable cover, so I can let excess heat escape on hot days - I know how hot those things get after having been a gardener for most of my working life.
I have never done the hydroponic thing before, so will buy some books to check out soil mixes & fertilisers, which I assume a book on aquaculture doesn't cover?
Will take a look at your thread Monya.
What kind of fish are we able to grow in Melb?
I am in Pascoe Vale South, quite a sheltered garden, no frosts. Can you grow Murray Cod or Redfin? (I grew up eating these

Jim's system has redfin, Minnamurra Aquaponics in Kinglake has Murray Cod. Muzza has some too. Definately no problems for silvers, murray cod, redfin in Melbourne

Your on the right track... Joels book is a combination of hydroponics and aquaculture, hence aquaponics. If you are doing a fully aquaponics system there is no need for fertilisers or soil. Thats where the fish come in.

Once you read the book it will all make sense, also have a browse through all the members systems here in the forum.

Hi Vegie girl if you want to see systems close handy steve has one in glenroy and mine is in sunbury

Well, my secret is out!

LOL i might even know you, grew up in oak park! how far from the 7/11 are you