Backyard Aquaponics
A place to discuss aquaponics

Think head is probably significant Stuart .

Figures for head are usually shown for pool pumps at zero friction. Pump crap and look at build up on the pipes, how do they perform?

Can the Laguna handle 10mm+ solids Stuart.....

Joel has spent considerable time putting together systems and components that WORK and work reliably over time.....

It's not just about price..... it's more about functionality and reliability.

I'm trialling some new pumps right now in some systems at the shop, they are quite low wattage for their flow and seem to work fairly well, though they do tend to loose flow rate fairly quickly as you attach more plumbing. More frictional losses rather than head issues.

I haven't done over head plumbing in a long time, which brings me to a point. A friend of mine once told me that it doesn't matter how high you pump the water, if your pipe outlet comes back down to a lower point, your head is really only from the surface of the water body your pumping from, to the height of the pipe outlet. Seems a bit strange to me...

Earthbound, I think your friend is right once the pump overcomes the initial startup head. Once over the hump so to speak, it would sorta siphon. What I have found is that when a pump is on a timer or float switch the pump must still overcome that initial head. Still not an insurmountable obstacle. I have put in a one way valve just above the pump to hold the water up in the pipe. My thought was the pump wouldn't have to work so hard to fill the pipe everytime.

I wonder if your outlet is lower than the pump, could it autosiphon your whole tank dry even if the pump is off?

Rup asked



Apparently the Laguna 11000 handles solids up to 8mm the Laguna 16000 handles solids upto 10mm.

Sleepe said:



I was aware of that. When I did calcs (with help) for fiction loss of one system design it required that I had an effective head which equaled height plus 4.5m due to friction loss. I reckon I can reduce the friction loss by pumping directly to a gutter from the sump. The gutter (or very large pipe) would then return the water to the FT. THe pump only has to get the water through a short straight vertical length of pipe. Would that work?

EB what are the pumps that you have been trialing? I am going to have a system based on one 10KL FT and eventually 20KL of growbeds. If I am flooding and draining the GBs once an hour I am going to need to deliver around 10KL/hr into the GBs.

Unless its a positive displacement pump or you don't have any breather the answer is yes.

Stuart

I assume you will be gowing FT-GB -Sump by gravity. To pump to a trough/large pipe then the large pipe will be inclined slightly towards the FT for return? To do this you will have to be pumping to a greater head than just straight to FT? If you pump to that greater height to start with then same sized pipe (not vented) to FT you will be getting the siphon action on the downward leg. Only advantage I can see is easier to clean.

Yep thats right Sleepe



Since the FT and Sumps are at oposite ends of the GH I thought that an extra "bit" of head would be less than the extra "bit" of effective head caused by the friction in a return pipe from the sump to the FT.

OK Stuart

Haven't got a clue

Think it would need an engineer a physicist, biologist etc. to work that out.

Hi all Just starting to bring the threads together for a system i have ordered a fish tub and grow beds from Darren Scott soon to be Aussie Aquaponics tank is 2275L and 4x 594L tubs I intend to gravity drain so only want a flood pump my only issue is my place is stand alone wind & solar so want a pump that will do the job but doesnt use to much juice am considering putting in extra square wave inverter that me bikie mates got left over from converting to pure sine wave my current inverter is a 1500w pure sine that will run 100Amps max however when your using house pump or microwave ect the last thing you need is for a AP pump on a float or timer kicking in unannounced. I run a doz 80w panels and about to install u beaut 500china wind geni pretty windy site up on a hill facing N/E can see the ocean its 7k away. So all you learned AP ers what you reckon?

I was looking at an ONGA VF150 and saw this in my searches....
http://www.recalls.gov.au/view_recall_d ... Auto=15242

earthbound,please DO NOT believe that about outlet height,,,it takes energy to raise water ( nothing for free in this world).
Pump "head" is a calculation of the rise in height and the addition of pipe flow resistance. There is a way to calculate pipe /pipe fitting resistance but uneccesary in this forum.Just use as large a pipe as you can have smooth curves rather than right-angles and raise the water as little as possible.
Efficiency of pumps varies but the major thing is to remember it is easier to "push' water rather than suck water , so submersed pumps are better.

Rohan

How about going a smaller continuous running pump. Least you'll know the continuous draw, and no capacitors to give you those nasty spikes.
Hope the wind geni is not from the same place Tony got his from.

how do you think a boat bilge pump would go ? used one in a hydro setup years ago and it was a tuff little bugger. Would use a seperate self contained power system if went that way. Whats the go with the wind geni Toni got is he the fella from WA with the huge solar sytem that bought a 1000w geni ?

just had a look and it is the solar sytem that i thought has he had a drama with wind geni might just be the controller apparently lot of the china controllers are shit and dont even work an alternate aussie made cotroller available on ebay my fatherinlaw is a electrickery techi swiss bloke going to get him to give the operating system a dose before i install there are a few things to consider with wind you cant just shut them of when batteries are full have to divert charge to dump or geni craps itself unlike solar panels also cant run them through the pl as far as i can assertain going to get my installer to sus it out as well before i plug anything in.

Rohan



Link http://www.backyardaquaponics.com/forum ... &start=105

Not pretty