Backyard Aquaponics
A place to discuss aquaponics

We're only talking 1m higher, is that such a big deal?

Don't anyone say the "eff" word....

When a pump only has 2m head, yes.

My pump goes to 3 different heights and to different size growbeds. It's alot of fiddling around and I wish I had set it up differently. I'm about to try to change it to a constantly running pump flood+drain by removing the timer and installing loop syphons. I will still need to make some adjustments to the flow but I think it will be easier overall. It means my electricity use will double, but the only other option I can see is to get a bigger pump which will also cost more. It's part of the fun, and keeps me interested.

Ideally for this system you would pump up to a header tank to make the flow control easier - but this cant be done due to weight issues.

The best option is to only pump the required water up to the extra height, all other water going to the lower beds.

KE different pumps are designed for different heads, its to do with the shape of the impeller. Most people just look at flow and think that moves a lot of water, when your pumping to head you should be looking at the graph on the box. It pays to go with a pump that is designed to pump at your required head hight. Personally I believe you should match your pump to your max head height required. (and a little more flow than you think you need )

My pump is rated for the head I'm sending it to. The problem is balancing the flow to all of the GBs of different sizes and at 3 different heights.

So from the pump where do the pipes go and where are your tee offs and control valves? Its easier running to head and controlling from there.

The dynamics of pump flow and energy costs is pretty complicated and in practice, more complicated than on paper. Stuff grows in the pipes and what works well at first won't work for long once the growies get working. Your best bet is to have smaller pumps, one for each grow bed, or do what I said before. Pump it up high, then drain it down where it is easy to control.

the most important thing to do is to optimize pump flow
the best way to do this is to (slightly) over dimension the standing pipe on the pump's exit and only pump straight vertically upwards to the height of the upper growbed, so that pipe length is kept as short as possible
from there, let gravity work for you in wide, all horizontal pipes or gutters
in the vertical stand up pipe you can have tee's at all necessary levels, each with it's ball valve (or slide valve for better adjustment)
after the valves again only wide, all horizontal pipes or gutters

for sequential filling of the growbeds, take a look at Novaris's system:
Car door actuators open or close the flap valves
viewtopic.php?f=18&t=3693&st=0&sk=t&sd=a&start=15

frank

Couple of questions Frank
I assume the slight oversize in the pipe from the pump is either to compensate for the effect of laminar flow or build up of crap?
What does "in the vertical stand up pipe you can have tee's at all necessary levels, each with it's ball valve (or slide valve for better adjustment)" mean? If your pumping to efficient head initially, schematically where does the vertical standpipe fit in?

no, it is to avoid all pressure buildup
the fact that it is vertical makes it very easy to clean, so crap buildup will be easy to remedy

a drawing says more than a thousand words:

zoom in and out with ctrl+ and ctrl-

extra advantage: all eventual overflow will simply fall back into the sump

frank

A picture says the same thing too.
Any thoughts on pumping to a large tank that can be used as a swirl filter and in case of a power outage the volume in the tank could still keep the system going for a while.

Agreed Duff if you can use the 'wasted' energy (ie tapping off lower down) to be useful, it makes more sense to pump all to head.

Here's an interesting one, what if you used a pump rated efficient at the middle GB and pumped in a closed loop with valves at each GB the lower ones on the down part of the loop, would the part syphoning action allow the pump to have a more efficient head?

Personally I still prefer the idea of pumping to head with the lower GB's on a gravity fed down pipe for two reasons (1) I have a great deal of problem getting my head round the physics involved in flows being interrupted on the up pipe and (2) It always seem easier to balance it this way (the more important reason for me).

Frank, this is a discussion