Backyard Aquaponics
A place to discuss aquaponics

Hello everyone
I've only just joined the AP wagon and after registering and introducing myself last week I thought I'd star a member's system thread for my experimental project with AP.

I'm picking up 3 IBC's on monday and will probably use only two for AP: I was thinking of having the following setup:

1 IBC as FT (900L approximately)
1 IBC cut in half for two gravel GBs
1 pump
spray bar for oxygenation on the return to the FT

I'm thinking of running Constant flow or timed FnD, since it is my understanding that a bell siphon requires the system to be at the exact same height and I cannot be sure of that just about now.

I'm yet to decide on the pump: I have been looking into both aquarium pumps and pond pumps; what is the ideal water turnover in one hour for this kind of AP system?

I will stock lightly at first, with native (or adapted/invasive species) italian freshwater fish (carp, catfish, pumpkinseed fish, and some other european fish).

Second newbie question: is it good to have biodiversity in the FT or is it better to have a single species of fish growing out? I mean, if I wanted to have, let's say, 40 fish, and have ten of one kind each, would it be better than 40 fish of the same species?

I'm also considering setting up a "mirror system" in the attic (plenty of light) for the winter where I can move the fish and plants from november to, let's say, february. We had -4 C for one week last week). I will think about this later.

My biggest problem right now is deciding exactly where to place the system, and am devising different solutions for different positions around my house/garden.

Last question: crab. A guy is offering them 3€ each, which seems quite a lot to me: are they easy to raise or will they fight with each other and/or become pray to the other fish?

Thanks to everyone in advance!
Last question:

Hi Tojo!



I don't think that is true, as long as each siphon has enough downpipe to work reliably and the inlet is split evenly above them somewhere then their heights should not matter.

viewtopic.php?p=78276#p78276

This was in my basement, one inlet split into four, with two tiers of small gravel beds with a loop siphon each. As long as there is enough drop for the loop (or pipe siphon) then they work fine. Maybe that tidbit of info only relates to a single siphon shared between multiple beds.

still timed fd is the way to go or cf you can't beat cf for simplicity

Thanks Dave and Nat. I will have a read on that link tomorrow.

I agree that for the time being CF is quite simple and the right choice for me: it is also my understanding that a Cf system can be easily converted in a bell-siphon system by adding said syphon over the standpipe.

Another question about the standpipe: does it have to have a small hole at the bottom to ensure it empties during timed FnD or CF? I read about said small hole on the forum here somewhere.

If you are doing FnD without a siphon you would need the hole to achieve the drain part of the cycle.
Also pumping volume i think is recommended to be shifting the total water volume in your system every hour.

Stocking lightly is a wise move, and as for mixing species it is not impossible, but there can be many problems such as one type eating another, or out-competing them for food so most people would advise you to stick with one species at a time.

It's my understanding that the classic internet motto "pics or it didn't happen" is a leitmotiv on this forum, so here are some pictures of my Monday achievements.

These are the three huge IBC's I bought today. They somewhat exceed expectations standing at 120cm width, 100cm depth, and 117 cm height and I loaded and unloaded them all by myself. One will become a rainwater harvesting system (directly from the gutter).
Is this the standard size for IBC's?


These are the other achievement of the day: quite cheap, but I had to unload them myself from the truck, which sucked. Anyway here they are, 14 bags of 33 L lava rock (pistillo vulcanico in italian), which makes the total of 462 lts of lava rock. If my 60% media and 40% water understanding of the GB's is correct, one of the two GB's will probably need a few more bags (I actually saw Expanded Clay at 1.60€x10lts, which is a great deal but they had like two bags...)

Forgot about this:



previous content of the IBCs: sugary mix used to make candies/sweets. It is totally food grade (the guy who sold them to me actually scooped up some and ate it in front of me, and had me try it!) It's so good and so sweet that it's almost a pity to throw it out, hehe.

Density about the same as honey. Shouldn't be a problem with some hot water.

BTW company is "Schutz", German.

I also scored this little guy (they were throwing it out, it's about 80 lts); any idea of how I could integrate this into my AP design?


Question: what is the standard diameter of an IBC cap?

Some news, if anyone carez (apparently not)
Bought a nice pond pump with three year warranty rated for 3000lts/h with 220cm maximum height (220cm=0lts/h)
I also decided to go for common carp and ill be getting them by the end of march.
Cutting the GB IBC tomorrow.
Still trying to figure out how to support the two GB's.
Some sparky work being done in the garden on thursday to have a safe, water proof and water-protected outlet
In the meantime clearing some space for the system.
I think it's still too cold for the bacteria population but I will still try to start cycling.

Cheers.

Hi Tojo
Welcome to the (addiction - ooops) forum. Looks like you are in for a few busy days.
I see you are contemplating putting an AP system in your attic Thats a lot of weight to have above your head.

Your IBC's look to be the same or very similar to ours.
The black bin would make a good step-up or else store your fish food in it

Looking forward to seeing your progress ...

Thanks Rrjl! I have, of course, re-thought about this and am only going to make a smaller, 150/200lts system (the house is pure concrete so it can hold that weight, of course) for the more temperate-climate fish for the winter (pumkinseed sunfish, will probably have about six/eight) and to keep going with some vegetables even during the winter, while maybe adding some trout in the "outside"/main system.

Thanks for the input!

Welcome. As to your original questions. For a CF bed, you don't need any holes in the stand pipe. Simple!

I don't know about different types of fish, but I've heard that crayfish "output" different types of nutrient (more Phosphorus I think?) than fish, so... good for a varied diet for the plants!

My only concern is other fish trying to eat them and the things I've been reading about them being agressive to each other: how many should one stock in an IBC (complete, non-cut) with other fish? Also, I was reading about giving them some hiding spaces with pvc pipe, I will have to look into that.

Look forward to seeing the finished product mate, if your going to go down the siphon path i can recommend the affnan siphon enough, very simple to make and easy to adjust for GB water height. I played with some of the other designs but they were all a bit fiddly for me, the affnan just works.

Thanks for the input: I'm wondering, if I were to start with CF, how difficult is it to later convert the standpipe into a bell siphon by adding the 'bell' part? Have you tried it maybe?

I haven't done IBC's but I was surprised the first time I saw them in a picture with something else for a size reference. They don't look that big in pictures!

You could use the trash can as a sump (if it holds water and is food grade) or as a rain water holder.