Backyard Aquaponics
A place to discuss aquaponics

Hey Aussie... good to see you back online... how about an update in your system thread...

Just thinking, that if I need a sump that large maybe I'd be better going with a system setup like the the BYAP family system, which only has a 500l sump. How does that get away with it? Is it because of the the two pumps? Presumable one pump pumps from the sump to the fish tank, and the other pumps from the fish tank to the growbeds?

Is this where you have problems if there is a leak? your fishtank pump keeps emptying and no water is making it back to the tank?

I have a 6 bed BYAP system and I have had several problems with the sump:
- had several power failures on my street, a few of which when the main pump had just filled the beds, lost quite a bit of water as the sump pump had no power to get the water back to the main tank.
- sump pump died (Ebara so was a good one), main pump emptied fish tank.
- new sump pump float cable became dislodged, thus didn't start pump, sump overflowed and again main pump emptied tank.

At the end of the day, no pump is 100% reliable, and my aim is to get my setup to a point where if a part of the sytem fails, not all is lost, and at least I have some time to rectify (ie. when I get home from work).

I'm currently trying to work through options of solving this, don't want to put 2 pumps in the sump, and the idea I am leaning towards is SLO (solids lifting overflow), as this limits the water loss if something goes wrong.

The sump is the weak link, and I have had a few other ideas (pump relays, etc), but they all cost too much, and make the system more complex, I'm a big fan of the K.I.S.S. theory.

I have approx 120 small silver perch (approx 5cm) in my system, and I'm losing sleep at the moment after almost losing the lot 2 weeks ago.

Happy if anyone else has some suggestions.

OK, so that explains it - there are problems!

So if I go with a large enough sump (although Aussie's seems a bit extreme), have a pump in the sump, overflow from the fish tank. The worst that can happen is that the pump stops, the fish die from lack of oxygen. (And eventually the plants die from lack of water if the outage is long enough)

So to protect it:
- have some other form of aeration for the fish tank (could run all the time)
- have a second pump in the sump (with something to trigger it, or maybe the pumps work for a hour/day each. Chance of both failing at similar times is minimal?) Maybe second pump is battery/solar powered?

Should result in no water loss, and a relatively "safe" system?

Just for info... the BYAP Family system... has a 1000L sump... two pumps, fish tank pump operated by timer...sump pump by float switch...

Ok, here's version 4!



I think it's a good intermediate step, leaving us space to put a second system in later, or to extend this one.

The fish tank is still 2700 litres, the four growbeds add up to 2700 litres, and the two inter-connected sumps are 2030 litres total (75% of the growbed volume)

It's a CHIFT PIST, with a pump in one of the sumps. The two sumps will be interconnected. The fish tank will gravity-drain to the growbeds, the pump will be on constantly, and the growbeds will drain using siphons.

Max stocking density of 3kg/100 L gives us 54 1.5kg meals - so a good one meal/week system if all goes to plan!

I'm now feeling disturbingly optimistic - what's the next thing I've forgotten?

andrew,

If the power fails in my system and the growbeds are full of water they just drain back to the sump and i lose no water. when the power come back on on it all starts up as usual. no real problems unless the power outage is more than 4-6 hours. The power has gone off here several times for 1-2 hours and all is ok and when the power comes on we are back in business. A large sump will save you from water being wasted. The 2 sumps you have designed in your latest drawing will be ok if they are interconected. you just have to make sure that the volume of water from the fully flooded growbeds will not overflow the sump when fully drained(assuming you are still using one pump in the sump) (Rupe will update my thread soon)

Aussie

Thanks Aussie, good to know - that's the sort of redundancy I'm after.

And the fish are still OK after 1-2 hours with no pumping happening?

andrew i use an airpump in my tank all the time because it is overstocked. I have left it off for 12 hours once but the pump was working and so it supplied some air as it moved water. When the power is off for 1-2 hours the fish have all been ok.

aussie

My BYAP system came with a 500L sump, so that may have escallated my issues...

From what I have read, and seen with my system, if you build the system to gravity feed to the beds, and put in a reasonable sized sump, you have a pretty robust system.

In any of the venturi drain type systems if the power goes out the water you lose will be the volume of water that is above the fish tank outlet, plus the water in the beds, minus the water your sump can hold (thus why I assume Aussieponic has such a large sump, which I am very gealous of by the way).

Therefore the fish will still have water, and the additional air you suggest will keep them going.

My BYAP system has a battery backed up air pump to provide additional air to the fish, and I can definitely say this is great, it's good enough to keep the fish alive in a prolonged power outage, and as long as the power comes back on within a few hours you should be ok. On battery power the air supply drops, but any air is better than none, especially as your fish get to a reasonable size...

Additional sump pump, your call, IMO I would keep the second pump as a spare if you have the money, as the system you suggest would only lose a small amount of water if something happens to the sump pump, and you can then just install the spare and top up the small amount of water to get it going again. But I suppose is good for when you go on holidays (if you get any that is )

The solar backup with a relay sounds good, but likely expensive. I was thinking of something similar where I put a high level sensor on my sump, so if the water reaches that level it cuts power to the main pump (regardless of the timer). You could do the same for your backup I suppose, and use the sensor to start the solar pump (or additional pump). FYI most people seem to use bildge pumps for the backup from what I can see, and for your likely low flow from bed system, these would be excellent.

"newfarmer"
"In any of the venturi drain type systems if the power goes out the water you lose will be the volume of water that is above the fish tank outlet, plus the water in the beds, minus the water your sump can hold (thus why I assume Aussieponic has such a large sump, which I am very gealous of by the way). Therefore the fish will still have water, and the additional air you suggest will keep them going."




My fish tank is an aquaculture tank. It has a central pipe,rising from the bottom of the tank to about 150mls below the top of the tank. This maintains the water level and keeps the tank from draining if the power goes out. So the only drain if power goes out is from the grow beds. I have 10 grow beds that hold with the gravel about 3500lts of water. I need a large sump to make sure all the grow beds are fully flooding. The fish tank never drops its level.

Aussie

I'm currently going through your thread AP - haven't got to page 57 yet

From early discussions on your thread I'm wondering if my 1.2m wide growbeds are going to be too wide to harvest across from one side. hmmm.

Yes 2.1 mtr wide grow bed is a little hard to harvest if only accessing from one side. I have allowed access from both sides.

Aussie

Only 1.2, not 2.1 :-) but I think double access is going to be necessary - back to the drawing board!

OOPS MY MISTAKE 1.2

Aussie