Backyard Aquaponics
A place to discuss aquaponics

Does that make more sense? Water flows all the time now, not only for 3 minutes an hour. I'm just filling a tank at the top and letting it drain. I'm using the same pipe for filling as draining to flush the air out each time.

the only reason there are restrictors, is to even the flows out to each to the tanks.

Kuda

Still be careful with the pump switching. I have a 260 lpm which only draws 1500W continuous running as per the specs. However rating on the label is 240v 12-13 amps and 1.85kw for the motor. I am assuming and no doubt someone more familiar with this can tell us, that the capacitor draws one hell of a current to kick her over. Perhaps Steve can give you some ideas re the float switch as air con systems (and air compressors) have a similar problem.

hmmm I was thinking a microswitch would do it, but perhaps you are right. I will speak with the sparky here at work and see what he thinks.

It makes sense, and it's a really innovative design, but I would just go for a smaller pump rather than a big one with headers acting like capacitors. The more complicated you make it, the more can go wrong. Of course you've already got a big pump, but it may still be cheaper to buy a small pump as you wouldn't need to buy all the parts that are required to run the big pump.

A small pump wouldn't work, one because it doesn't allow me to upsize easily, and two because it doesn't have the power to blow the air out of the pipes, so an airlock in the output pipe can actually stop a smaller pump. That is really frustrating, as you have to ensure the pipe is either completely empty or completely full.
I have apetrol pump at the farm, and that wont pump up the hill if there is a head of water there already... It creates a tiny airlock itself I think.

as far as pumps go, bigger is better. I think EB says this in his DVD and book too.
(hehe namedropping to lend creedence to my own statement thanks EB)
bigger pumps don't fail, don't block, don't do weird stuff, and always pump enough. (until you get too big for your boots)

If the smaller pump is always on, then you shouldn't get the air lock in the first place. Maybe someone who's of the CHIFT PIST camp can tell us if they've ever had problems with air in the pipes for continously on pumps. You could do some simple stuff to minimise the chance of it happening though (e.g. simply angling the pipes so that air bubbles come out the end would do it - you could do it for your grow beds, but not for your pond. There are other things you could do for that though). I guess if the power went out and then back on then you could definatley have a problem.

Anyway, moot point if you want to expand later.

You can get small pumps which are super reliable. I've had an small eheim running in my computer (yes my computer is water cooled) for ~5 years and it's never failed me.

Probably wouldn't handle solids too well, but you can use a venturi to do that.

I've also been wondering about energy consumption. Will a large pump that turns on periodically chew through more electricity than a small pump that is continously on? (Transfer the same amount of water the same height of course) i.e. Is a large pump more or less efficient than a small pump? Or is there no general rule for this conundrum?

Gemmell

Horses for courses really. Kuda is running a 3m head. Small pumps that can do that efficiently are pricey and running close to max load. The Davey shouldn't even break a sweat. No one seems to have 'solved' the continuous pump run intermittently reliability issue, however air compressor motors seem to handle it without a drama.
One advantage of his way is the built in power-cut safe margin.

Power consumption ???????? My big pump will pump to a 30m head max so think its a height thing.

All Kuda needs to do is be very nice to F&F so he has a back up pump .

I'm sorry Gemmel, and Rupert. At the moment I don't have any growbeds actually plumbed up (this was only mentioned in fine print) and I plan on increasing my growbeds slowly.
For this reason, I need an easily expandable system, and a pump that can handle my final phase.

As it turns out, I think this pump will not be adequate - yes that's right :-)

I have done significant testing this afternoon, and found that 3 minutes on, 20 minutes off is the rule for now.
Also I believe I need to increase the size of my sump, because I it takes more than 20 minutes to drain, and uses half my sump.
So my pond wont be able to inflow continuously

so it looks like a bigger sump is required but I should be able to add one on without too much trouble.

oh, and F&F always has new pumps available, he can sell me another (or a bigger) at his leisure.

Shop is open all over xmas

Surely you're not paying the workers penalty rates?

Fair enough. As you say though - Horses for courses.



Hijack, but I was wondering if a pump which pumps 100L water to a height of 2 metres in 3 minutes would consume more or less than a pump which pumps 100L to 2 metres over 10 minutes. I doubt there is a hard and fast rule though.



I had a similar problem with my sump size (but mine was 70L!). Next one will be 500L. It seems to be that the bigger your sump, the more robust your system.

it SHOULD require the same power as the 3x stronger pump is only on for a third of the time (lets make it 9 minutes, hey.)

of course differing motors will throw all this out.

you can get a pump motor that is 55% efficient and then you can get ones that are 85% efficient

yup, there was a hijack asking the same question in another thread very recently, try searching for that...

Pump does not run continuously. Header tank is to ensure continuous flow to pond & tank for aeration and mixing consistent water quality.

Pump runs 4 Mins on, 20 mins off (atm with no GBs) - However, it will be sump float activated, not timer activated.

GBs will have timed solenoids or actuated gatevalves. so that I don't water log my plants. The header tanks will supply the GBs also.

please reference these Drawings

Pick apart this post, and tell me what I haven't explained properly. I sometimes have trouble understanding where a question is directed.