Backyard Aquaponics
A place to discuss aquaponics

OK, looks like I can get a couple of IBC's.

I've been trying to work out how to put them together.

I thought up this design and thought I'd draw it up and let everyone have a look at it.

I really like the idea of not putting holes in the sides of my IBC's, if there's no holes there's no leaks.

How it works:
Pump in sump pumps to 1st IBC
Water level equalizes through water bridge into 2nd IBC
Water 'over-flows' from 2nd IBC into growbeds
Auto-syphon drains to sump
Around we go again.

Thinking about having the pump on a float or timer, I'd rather a float.

I need to work out how much water my growbeds will hold and therefore how big my sump will need to be but I'm not too worried about that at the moment.

OK, here it is.

I`m doing the same sort of thing but instead off a water bridge I`m linking the ibc`s through the 2" outlet`s at the bottom then up to fish tank water level
(with a breather to stop siphoning starting)then overflow to beds.

my only concern is with the bridge either failing or the joining pipe blocking up with fish or shit. or both best idea is to put taps and barrel unions in the pipes joing the two ibc's together so that they can be isolated and pulled apart for cleaning down the track.

Ah, I like that idea too. I had thought about drawing from the bottom but hadn't thought about a breather, that solves the siphoning problem I was worried about.

Your pic is very well done, that's sketch-up isn't it?

It is indeed

I was planing to put mesh over the ends to stop the fish going up there and getting stuck. Wouldn't have thought shit would block it but there is that law 'if it can go wrong it will' so I'll have to think about that.

yep, shit will block the mesh unless it is like 10mm squares. even then, the shit (shere's that word again) will stick to the mesh and slow the flow eventually, as long as you can get to it to scrub it it should be okay.

Join them at the bottom, savage. Have the barrel unions as Mon said. The ibcs will each have a ball tap, so every 12 months, u can close those, undo the joining pipe for a quick clean.
With ur overflow setup as per the pic shown, you may not get the solids removal into the gb. Having ur pump in one ibc will help that. Or tee off from the join at base if u want an inline pump from ur ibcs.
The overflow as ur leveller won't be necessary since ur tanks will be joined at the base.
Very approximate rule of thumb, 40%gb volume= flood volume on pump cycle, so a 1000lt gb would hold about 400lts at the height of the pump cycle. Say u had 2 blue barrels joined like the ibcs, as ur sump. In theory you have a max of 2400lts in ur system. Reckon you could easily handle a couple thousand litres of gb space.(That's 8 bathtubs!)You would have about 600lts in each ibc at the least which should keep ur fish happy.
You will need to put a small screen inside each ibc at the outlet to stop fish switching tanks(and getting stuck in the join.) That will be a prick of a job, but a oncer. Same if u used blue barrells for ur sump. (Then you can keep fish in there too!)
Sorry bout the waffle...

SG,

My only advice is to make your pipe/water bridge that is connecting your 2 tanks MUCH fatter than you think is necessary. I have a short (<50cm) 50mm PVC pipe connecting 2 of my waterbeds (aka bathtubs) together & it cannot handle ~25L/min.

50mm pipe seemed ample when I plumbed it as the supply from my 125L/min pump is 35mm PVC pipe in places (bottleneck) & only one-fifth of that (ie. ~25L/min) goes to the waterbeds.

The lesson I learnt is that the pressure from the pump accounts for more throughput than I intuitively thought.

Also, be careful of small air bubbles collecting in a water bridge. It might "break" the bridge - could be fatal depending on your setup.

It's a constant height in fish tank design (chift pist even!), so the water level shouldn't drop enough to break the siphon. Still, if you lose either the bridge or the overflow, you stand to lose a lot of water.
I'd suggest two bridges, in case one fails from a buildup of air in it. Just feel the weight of the bridge occasionally to make sure it's full of water (or make it out of clear stuff).
Also, the closer you can get to the base of the tank the better, so that you suck up solids from tank 1. Mine has a blue barrel full of gravel sitting above tank 2, with a pump constantly running water through it. This helps by:
1 Providing additional biofiltration
2 Providing constant aeration from the water splashing back into the tank
3 The pump removes solids from tank 2, which otherwise would just build up.

Joel has got around the 3rd point in his chift pist design by having the overflow inlet at the bottom of the tank as well.

+1 scottie

SG, believe me, fish will travel through 50mm at the bottom, until they're 100m long at least.
I had a 70mm goldie travel 20 metres through 25mm pipe with 10 elbows in it.
I would hook them up ath the bottom, if you want you can still put in the bridge.

TT, don't worry, your not waffling it's good info. The 40% thing is really useful. I was thinking about having something living in the sump, was thinking about yabbies so if the water level went low they wouldn't freak out like fish would. If there is enough water for more fish thats even better.

Scottie, I can well imagine the problem. I was going to use 4" or 6" storm water pipe but I haven't checked if it's OK for drinking water yet ether.

Since most people seem to think plumbing them from the bottom is the way to go thats probably what I'll do.

Anyone want to make a suggestion on the size of pump I should use? I have no idea.

I would just love to know what the goldie thought of that!

Well there was a restriction at the end. Goldie got stuck, pressure made goldie extrude where he usually wouldn't and goldie didn't survive long after the rescue
But we live and learn

The pump depends on the way you want it to work. Personnaly I wouldn't go for a float pump system, floats are not failproof.

So if your system is 2 x 600 L of FT (2 x IBC)

And your growbeds with a 2:1 ratio, are then 2400L with 40% water then 1000L approx. (size: 2 x (400 cm x 100 cm x 30 cm))

I'd say sump be little more than the amount of water in growbeds in case of power going of when growbed full then sump= 1200L . (size: 200 cm x 100 cm x 60cm)

With 3 cycles an hour= 1000 L / 20 min

Two solutions:

1/-Cycle pumping on timer: 3 x 5min pumping /h
1000L/5 min and 15 min drain
200 L /min then pump 12 000 L/h

2/-Cycle on constant pumping: 3 x 20 min pumping / h
1000L / 20 min and fast drain on next cycle (big piping)
50 L /min then pump 3 000 L/h

Good on theory, would go for a lightly bigger pump because of the piping and fittings decreasing flow. And if you do a venturi system at the inflow in the FT then you'll be decreasing the flow also.
So in 1/ better go on a 15 KL/h, fast water speed decreases more the flow
And in 2/ better go on a 4 KL /h


Don't forget to put an air supply in IBC when power off.
Would it be possible to plug an inside standpipe in the IBC bottom tap?
With a pipe in pipe standpipe you won't have any trouble with stuff deposit on the bottom.

Hope this helps