Backyard Aquaponics
A place to discuss aquaponics

Hi guys!

I would like to share with you my new aquaponic/hydroponic system. I'm a newbie in forum and in aquaponics/hydroponics too, as well in greenhouses... so I would appreciate some advice and help! I just want to avoid as many problems as possible before spend money Sorry for my grammar, I'm not a native English speaker.

I want a make a small greenhouse (5x4 m, 20 sq meters = 215 sq feet) in my garden, and my goal is to try to grow all type of vegetables, all year round, for my family (if I can..). I'm from Spain (temperate / mediterranean climate), so I think I can mantain a 21º C (70º F) water / greenhouse temperature without spending a lot of money.

I've been checking forums about aquaponia, aeroponia and hydroponia, and I found that vegetables grow better in different systems (NFT, Raft system, Flood & drain or Aeroponia). So I've decided to try all systems. (4 in 1)





I made the following logic to calculate the ratios.

The only part where the system delays the flow, is in grow beds. Both together are approx. 1500L (960 + 540). If 55% is occupied by gravel (bottom) and clays (top), there are 675L of water in grow beds. So is better than the typical 2:1 ratio, 1500L:1000L (1,5 grow bed : 1 fish tank : 1 sump).

But then, I found in another site that they are using another way to calculate the system:

I have 13,4 sq. m. / 144 sq. ft. to grow plant (including raft, NFT, aquaponia and grow beds). And I want to plant a great number of plants that are high nutrient consumers.

So at a ratio of 60-100 grams day/ sq. m:
13,4 sq. m. x 100 grams = 1340 grams = 1,3 kg/day

If tilapia at final stage weight 450 grams, and every day eats 1% of his mass. I have to give to every one 4,5 grams/day. So 1340 grams/day / 4,5 grams/day = 298 tilapias!!

And the optimal space for tilapia are 100 for every sq. meter. That means that I have to increase my fish tank diposit from 1 sq. m. to 3 sq. m., so from 1000L to 3000L (1 sq. m. = 1000L).

What I should do? Should I add another 1000L fish tank connected to the other one?

Do you think I will have enough pressure for run all the system, or I need a better pump?

What do you think about the system? May I have some problem with that piping / greenhouse design? I'm completly newbie, so I have a lot of question without answers..



thanks!!

Welcome

Are you sure that is for Tilapia, and not for Sardines? I think you meant every cubic meter, which means that each 450g fish will have one bucket of water - 10 litres, of water volume. IMO this is far too high a stocking density.

Also, I think that you will have great difficulty, and/or great expense, in maintaining your water emperature at 21C all year round. I have a 4500l tank buried in the ground in weather that has varied between -1C and 41C this year, probably not all that dissimilar to your conditions, and you can see in my system thread what sort of water temperature variations I experience.

Welcome ratafrita, but I can't see the pictures

sorry!! hehe.. I would mean 1 cubic meter can hold 100 tilapias,

I'll try to put images again, I don't know why is not working. ( I think is a resoultion problem )







I put the links, for any problem. And attached too!
http://robert.suitse.com/aquaponics/1.jpg
http://robert.suitse.com/aquaponics/2.jpg


I will have my tank buried too, and inside the greenhouse, so I hope that helps to mantain temperature a little bit. Sure I'll have to spend some money heating too!
What fish / tank ratio do you use?

thanks for your replys !

Mine's a new system, so I went with light stocking rates- I have ~80 rainbow trout in a 4500l tank, total system water including sump is 6000-6500litres... + 8 X 500l GBs.

My brain hurts. Seriously, 100 fish in 1000L might work in aquaculture with massive filtration but its not the idea in aquaponics. Good luck

The amount of fish that can be stocked... is not related to the amount of water you have...

It's related to the amount of filtration you have available for your potential maximum feed rate...

Yep, in the name of constant fish kills... (that apparently don't happen )....

I wish we could rid aquaponics of the 100 fish in 1000L myth nonsense...

Well, the only way to find out is to ask questions here. Where the info is good!
Don't feel slighted ratafrita, you've accidentally struck a nerve. The consensus here is that 100 fish/1000L is overstocking and isn't sustainable.
The others here will give you their experiences with stocking rates.
Otherwise it looks good, I like the thought and planning you've put into your project so far.
Again, more experienced voices will notice any potential pitfalls that I can't see in the design.

I said that (100 fish in 1000L) following a graph that I found. I suppose that was refering Tilapia in aquaculture ratios.



Anyway, How big should be my fish tank for feed 13,4 sq. meter plant area?






Thanks for the info! nice to know , somebody know some info. about how to size your filtration tank?

I just want to grow as much veggies as I can, with the minimum fishs. I don't have a lot of space for fish tanks (I can put 2 tanks more (2000L)).




thanks Bodgy!!

Just one other thing, your media beds will be what people mean when they talk about filtration.
If you are more interested in plants than fish you'll be happy to know that a small number (or weight) of fish can grow a surprisingly large amount of plants.
Again, I can only say what I've seen from others here. I'm still new myself and learning.

Oh, in case I led you astray, the water for your NFT or DWC needs to be spotlessly clean, might need some sort of filter to ensure that.

Very few fish are needed to grow a lot of plants

As a guide it is suggest that you stock 1 fish per 25l of grow bed filtration...

Thanks for all the advise

Do you think is ok 60 big tilapia for every m3 water? and is enough to grow 14 m2 of tomatoes?

Another question, I'm planing to make NFT part with a splited pipe, so is more optimum for plant space (there are no holes, is all a big hole), but I think sunlight may affect water and roots. Is this a bad idea?